Ok..Thanks for the heads up. I am in to rush to get the USA number to keep this thing going. Though I do need to get the Data Bundle renewal shutoff. Hopefully, I can get them to do that without setting up the USA number first.

3's coverage in HK is good IME.
In the UK I can receive coverage >95% of the time in London (except for some parts of the tube and in some buildings.)

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Like jsmeeker I used a toggle sim, but in the Netherlands, germany, austria, slovakia, hungary, and London. I had a local number for Netherlands and germany, and obviously London. I also got a US number. I could not pay for the sim on line so they sent me one. Topped up with 30, got my local numbers before we left, and put it in my phones. As I was testing, i had my old galaxy nexus, and a BLU dash 4.5 dual sim. The BLU worked great in the first slot, not so much on the nexus. I am not sure why. It registered after about 5 minutes at LHR and i checked emails. It very often would lose the APN so be sure to write it down or memorize it, as I had to put the APN 5 or 6 times on the trip. (google keep is your friend). After I put in the APN again in Amsterdam it worked fine for data and voice. Data speed ok for google maps. Germany was a bit of a problem as it didn't want to connect but after rebooting the phone and putting the APN in again it worked fine. It roamed nicely in Austria, Bratislava, and Budapest. Back in London I did not have too much trouble with data, as was mentioned upthread. Overall it worked ok for us and I plan to keep the sim alive for our trip to france in a few months.

I'm unable to find any info on a £5 top-up to allow unlimited international data in France. I did find this, which mentions their "Feel At Home" plan, which means that you use your phone just like you're in the UK (same package rates apply). That mentions Italy being included.

Did they drop this other international plan since your post, or am I just missing it?

Hi - will be in the UK (London, GB, Scotland) for two weeks next month.

Lots of info here... what I'm most concerned about is data quality (and not price) through GB and Scotland.

I'll have my unlocked iPhone 5S (VZW).

Who has the best coverages? Is there any chance of LTE?

I figure i'll use about 2GB of data in those two weeks.

No chance of LTE as your iPhone lacks the correct bands for the UK.

As for data, it really depends on where you are and the network coverage. If you're in urban areas 3 is as good as anyone. Further out you may struggle to get 3G - even with O2 and Vodafone.

That's not necessilary true. The Verizon 5s should support LTE on 3 UK.

Take a look at http://blog.three.co.uk/2013/02/20/s...-is-confirmed/

And
http://www.apple.com/iphone/LTE

Other providers may not be fully supported since the VZW 5s doesn't have LTE 2600

Well thats good news... Guess I'm willing to take a shot on the 3 UK network. I'll report back in late February!

I should mention if you're used to Verizon/CDMA 3G(aka evdo) the UMTS/HSPA 3G is a heck of a lot faster. My friend in London E15 gets 10mbits on 3G on 3.

3 Have only just started to trial 4G in London. The full rollout has yet to take place.

When I go to the 3 UK website, and look at coverage maps, it shows 4G in a bunch of places...

Pretty large rollout in London, followed by small rollout in Reading, Birmingham, and Manchester.

http://www.three.co.uk/support/Coverage?postcode=london

Has anyone actually used 4G/LTE on the 3 network?

My coworker has a 5s on 3 and has never seen 4G/LTE service. We were just talking about this a few days ago. He thinks the data service he will see in the US next week will blow his mind.

Lives in EC1 and works in WC2 - very central.

It can be very impressive. I recently measured 24.66 Mbps download with 73 msec ping time on an LTE connection. This was at home, where my landline DSL is not so impressive -- 1.85 Mbps download. Landline broadband is generally not great in the States. I live at the far end of DSL service, in a spot where the local cable company hasn't extended its service, so I pay for two nominally 3 Mbps DSL lines and use a load-balancing router to make them as useful as possible.

Oh wow - DSL?! You must have the patience of a saint. As for 4G/LTE, it's funny how we take things like that for granted here in the States where it is becoming pretty common. I thought my coworker was making up fairy tales until another coworker confirmed that the UK is a bit behind the US in that regard.

I dunno about patience -- we don't have an alternative, so we use what we can get. Our narrowband DSL was a huge improvement over what we had before: a 3G EVDO cell modem, with an external truckers' antenna, plugged into a CradlePoint router. :( That was before LTE appeared in our area, obviously. Now that we've got two DSL lines and a load balancer, it feels like the lap of luxury. And, if I'm in a rush, I can always use my phone's grandfathered "unlimited" LTE. (It isn't really unlimited, even though Verizon advertised it as such, but we've never gotten one of the dreaded cutoff notices they've been known to send.) :)

We can usually stream Netflix at HD resolution, and we just schedule big downloads to run when they don't hog too much bandwidth.