If you have any specific questions, why don't you post those? Asking if anyone has any info on UAG is a really loaded question.
I recommend you do a search on this site - there have been lots of posts about UAG. You can also check out UAG's unofficial forum at
http://www.netbabbler.com/goto/?forumid=7468
Keep in mind that there are a lot of bitter people who post about UAG (bitter because they didn't get into a US school and they can't take what the school throws at them -- it's not all good), so take what they say with a grain of salt. Also consider carefully anyone who is too "pie in the sky" about the place, because UAG DOES have a lot of faults. Basically, access this site, read a lot of the posts there and on this site, then weigh everything and make your own decisions about the place.
For the UAG line, see
http://www.uag.edu/opciones/medicina/med.htm
Basically, they charge tuition of almost $18k/yr, *most* of the instruction is in English for the first 3-4 semesters. They've just instituted a new "test" whereby we must examine a patient and take a clinical history, in Spanish, by the end of the 4th semester. If we don't pass that, we can't pass to the 5th semester. Even if you ace the Boards... There's a lot of bureaucracy, and you can't expect anything to be like it is in the States. Don't expect logic or forethought. Just decide to go with the flow (which many of us have trouble with...) or you'll go nuts.
Anything else?