My husband is going to start frequent travel between LAX and Frankfurt and Munich. He hasn't been traveling much recently so there's no allegiance to a particular mileage program. Could you give recommendations for the best airline to use based on their points program and just the quality of the airline in general? It looks like American and Lufthansa/United have the most flight options. Appreciate any suggestions--including another forum that would might be a better place for this post.

What class of service and how many miles does he expect to fly a year?

This forum has all the information you could possibly ever need, I suggest doing a search for those two airlines! Offhand I would say go with American, but you can check both their websites for the best deals.

He'll probably be traveling there 6 to 8 times a year and will fly economy.

Lufthansa. Clean planes, nice staff, and the planes run on time.
I fly that route a couple of times a year--I would not fly anyone else.

^

If he wants to fly non-stops and he (or his company) is willing to pay the going rate for non-stop flights to either FRA or MUC, then LH is the only LAX option.

If not, there are plenty of options besides AA.

Then American and United it shall be. Based on your subsequent post of 6 to 8 economy seats flights, try to stick to one or two airlines in order to achieve some "status". Miles credited to a few airlines is not a problem, and can ultimately be used for free tickets down the road.

As a UA flyer, are you getting the same bonus miles when on LH across the Atlantic in economy as you would on UA metal? On UA or AA that would be around 24,000 miles total on a round trip ticket if you're midtier or higher.

AA offers FRA from DFW or ORD. They do not offer service to Munich, so you'd have to use a partner (BA from London would be one option). You cannot accrue AA miles on BA across the Atlantic from the U.S., though there could be changes in that come October.

AA offers FRA from DFW or ORD. They do not offer service to Munich, so you'd have to use a partner (BA from London would be one option). You cannot accrue AA miles on BA across the Atlantic from the U.S., though there could be changes in that come October.[/QUOTE]

Do you mean that booking with AA to Munich you only get points to the European city where you'd change planes, say London, but no AA points for the London-Munich portion on the partner?

AA and partners can be a very intimidating experience. Depending on the fare class for the partner, you could get ZERO, 25%, 30%, 50%, or even full miles. Here is a link to the partners page if you want to look at how it all works out:
http://www.aa.com/aa/i18nForward.do?...lines/main.jsp

You would get full miles for the AA flight to London, and then 25% for a BA connecting flight. The AA wiki on FT spells a lot of the fine print out:
http://www.flyerguide.com/wiki/index...rican_Airlines

There is a workaround (book the AA codeshare London-Munich, though it may cost more).

One thing you need to consider, if travel will exceed 100K a year and that is ongoing, is upgrades. Both UA and AA offer systemwide upgrades for international travel when you reach that 100K mark (6 at UA, 8 at AA). Lifetime status is also accrued differently on either carrier (AA allows miles from all sources while UA requires flights on UA metal).

Don't rush into any decisions. Take some time to read about the carriers on their own web sites, too.

Thank you for all the input; it's all very helpful and you've brought up things I hadn't considered such as flying with the partners. I'm open to hearing more opinions/experiences.

I just did a separate post asking about the FFPs for UA and AA.