This is going to be moved to tools pretty quick. That said, I prefer EF as it has a regular site revenue fare availability function that actually works.

I use EF because it's web based. KVS though has availability for many many more airlines.

KVS is not web based?

Seems that EF doesn't show UA R class for upgrade availability. Does KVS a show that?

There are several older threads discussing the comparison of these tools:

No

ExpertFlyer has a free, no-credit card required, 5-day trial for their Pro-Premium version. Try it and compare it to KVS for fare class availability.

Those of you who still use KVS in the spring 2020 and also use currently or previously used ExpertFlyer as a paid service, how does KVS nowadays stand out or differ from EF? Is it worth paying for KVS as well, besides EF? Is there anything to gain as a FFP junkie?

I haven't used KVS for several years now, since I didn't see how it was better/more useful than EF. I would be interested to hear some recent comparative reviews regarding KVS, especially for oneworld and Skyteam use, but also AS and non aligned airlines.

Thank you!

I am not a power user but I do subscribe to both and can give you some information.

It's not that one tool is clearly better than the other. They both have strengths and weaknesses. EF is better for some tasks, KVS for others. I think automated alerts are where EF truly shines (when they work) but it has many other worthwhile features as well. With KVS I can have a base search and just switch methods to search multiple carriers/alliances very quickly so long as I am looking in a tight range. KVS is supporting more and more POS options on searches which can be helpful. JL for instance has some awards only available with POS Japan and with most search tools you will miss those US->JP POS JP awards. You can book POS JP awards via AA by calling their Japan call center and requesting POS JP. I like using KVS's Awards/VS method to search for DL awards. Searching on the VS website can restrict the origin or destination airports but with the KVS method you can type them in. The limited DL awards I've checked have been cheaper through VS or AF than DL. DL can really gouge you on the miles.

Downsides of KVS are that it mostly accesses your own accounts to search and I have run into more and more cases where you need to answer a captcha before a search proceeds and some carriers will throttle your searches if you do too many too fast (lock you out of searches for a period of time - I'm looking at you QF) which tends to handicap KVS's power search for some carriers. For AS I don't really see KVS having much benefit. The AS website returns queries quickly and makes for usually faster searches on AS than I can get through KVS, especially when considering the AS website returns multiple day availability and has a calendar search that will show you an overview of a month at a time. KVS has to have frequent updates to match changes in the carriers web interface which means you have to update sometimes before you can search (KVS will tell you if you are required to update before starting a search). EF being web based does not require user updates although certain features can break from time to time and EF seems less responsive to fix them than KVS.

Downsides of EF: I think maintenance on it has gone downhill since TPG bought it. I have run in to multiple bugs over the last few months which are not fixed unless I report them and then it may take quite a while for them to fix. Their DL award search was broken for a long time. Their EK award search too which I reported a week ago and is still not fixed. They claim it is a problem with their data provider and all they can do is report it to them and wait for them to fix it. If your provider is not responsive to you you should probably get another provider. I had set an alert for UA inventory on a flight for the summer and the alert never triggered even when the inventory became available. EF's response was that the flight time had changed more than four hours and their system couldn't handle it so they did nothing. They did say they may try to fix this issue in the future. I'm not holding my breath. I had two alerts set for a flight, a schedule alert and an aircraft change alert. The flight was canceled and EF never triggered either of the alerts. When I asked they said that a canceled flight does not qualify as a schedule change or an aircraft change to them which is why they never notified me. Hmm, OK, I asked them what alert to set to notify me of a canceled flight and they say they do not have one -- oops! When I access EF through a VPN it hits me with a captcha for almost every search I do which is annoying as heck.

So, I like both EF and KVS for different reasons and I see enough value in both for me to subscribe to both but depending on what your needs are you may find one or the other more beneficial to you.

First of all many thanks for your awesome and detailed overview of the situation, skimthetrees!

So you mean currently one can't try to find efficiently partner awards with KVS, unless you have a respective FFP account (let's say DL for being able to find what I might be able to redeem with AF/KL or AA for being able to find what I can redeem with BA)? That's not exactly practical. In terms of awards, my biggest headache is finding AS and AA partner availability with BA now, which is quite doable with EF. I know COVID-19 has screwed up the redemption game as well, so it probably explains the current issues I've had with planning any QF First experience, so not assuming it's due to EF having a handicap.

Have you been able to pull successfully fare rules and routing tables for any fare basis with all OW and ST carriers, using KVS? That seems like a constant issue with EF.

Not just awards, but DL flight availability as well.

I agree 100 % with you! It's annoying with any hotel, airport, lounge or other public Wi-Fi, not to mention satellite Internet on board a plane. Yes, I use VPN outside my home network in all circumstances, so it's indeed annoying when trying to troubleshoot in a hurry some last minute reroute. I can easily remember e.g. my frustration last year at MIA, trying to figure out how to reach the other coast, when things go haywire with your itinerary and you have to look at some school buses and what not. Yeah, been irritating quite a few times and especially when you really don't have many minutes to decide. When it works, it's nice that with EF you can then easily also pull up the seatmap to see which seat you can request from e.g. an AAngel ("could I have AA2 and seat 8A, please?"), while doing the reroute.

I think I will have to give a try for KVS again. If award data is indeed ample and there's no issues with fare rules and routing tables, then it sure sounds like my biggest current gripes with EF would be solved. I do indeed use EF for award/upgrade and seat alerts, which OTOH could be solved by other means as well.

I don't use the fare rules and routing tables so I do not know if those work. A quick pull of fares on one route left me wondering where OW fares were. If you can't find info in the KVSTool site help you can PM KVSTool for help. If you do sign up you might try a 2 month contribution first to see if works for you before committing to an annual one.

To search for most awards with KVS award search methods you need a free FF account for the program you are searching. It's no big deal to sign up for free FF accounts (like BA, QF, AF, etc) for award searches. You don't need accounts for most of the non-award searching. Some award searches you do not need one, like AS I think.

When I used EF I really like that they use Sabre to pull fares + available space. KVS always tried to screenscrape some websites to pull these free of charge, as soon as 1 loophole was closed they found a new website to exploit. But that was then, not sure where they get their data from nowadays.

Yeah, that was my gripe as well with them, back when I used KVS for the first time for one year. At least it sounds like scraping, if you need to create FFP accounts.

I've understood they'd be good for finding awards, but not sure I want to create n+1 FFP accounts for that. As for AA redemptions, the availability has gone quite a lot for the discounted redemptions, which partners can book, so not sure KVS will be any better for hunting those.

It is not a huge deal to sign up for free accounts for a few FF programs and those I believe are only used to get award availability for that program and possibly pull up enhanced seat maps for elites. You can get a lot of use out of KVS by having one FF account per alliance, so three minimum for the three major alliances (Star, OneWorld, SkyTeam), and I am sure you already have at least one of those accounts. If you want to check more programs you can sign up for free FF accounts for those programs. You sign up once and you forget about it. No big deal. The only annoying one is M&M (one of the 4 *A methods) since it now requires you to have a small amount of miles in its account for you to do M&M searches, but there are 3 other *A methods so it's not a deal breaker.

I don't believe non-alliance methods require an account (don't need one for AS, VS, EY).

The fare rules are not pulled from FF accounts so I do not believe you need an FF account for those (check the KVS FAQ, it may have more info). If you have specific concerns not addressed in the KVS FAQ you can PM or email KVS.

If you are not getting the info you need out of EF then it probably wouldn't be a bad idea to sign up for the 2 month KVS so you can try it out. Then you can go annual if you find it useful.

You are right about AA awards. KVS does not provide info on non standard AA award levels (no way to look for AA web special awards). It does get information directly from DL and AF (free FF account required) so it will list enhanced DL and AF award availability.

I have significant concerns about the privacy of my queries, and the integration of ads and data collection etc - on EF.
Check the terms and conditions of EF

Caveat emptor

If you have questions/concerns all you have to do is ask. As I'm sure you noticed EF doesn't have ads onsite and we do not sell user data to third parties.