Chocks,
I did mine at an FAA school, and had no problems.
Basically, take with a copy of LASORS or something similar so that you have the exact requirements in front of you, because your FAA instructor will not know what the requirements are. Then, make sure you meet all of the requirements.
When you send the paperwork to the CAA, you will need your instructor's signature. You can get the form off the CAA website and take it with you so that your instructor can sign it while you are there. Or, if you forget, just fax a copy of the appropriate page to your school once you're back in the UK and get them to fax it back with the instructor's signature - that's what I did, and the CAA didn't seem to mind.
If you do your training at an aifield with ATC, don't be surprised if the controllers query your stop-and-goes, that seems to be a UK-only idea which American controllers have never seen, but they will be able to accomodate you!
There was a query about the legality of solo flight at night when I was there. Assuming you have an FAA license based on your JAA license (which is the most common way of doing things), this license will not allow you to fly at night in the US, because your JAA license doesn't allow you to fly at night (at least not yet). So you will require an FAA student license in order to be able to fly solo at night - and that means all the usual restrictions on student pilots, e.g. no carrying passengers. According to the FARs, you will also need an FAA medical - your JAA medical is good when used with your FAA license based on your JAR license, but not when used with your FAA student license. However, the CFI at my school spoke to his FAA representative, and told me that the FAA are aware of the problem, and they are quite happy for you to fly solo at night on your JAA medical - they intend to update the FARs at some point to represent this but it's way down on their priority list. You might like to get an FAA medical to cover your back.....
Not sure about the Visa requirements. I didn't have one, but thinking about it, I suppose it is training, so it should really be required. But if you're in the States doing a whole hour-building package and the night qualificaiton happens to be part of that, I don't think anyone would pick up on it.
Finally, don't take anything I say as gospel - it's well over 3 years since I did my night qualification, so things may have changed since then.
FFF
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