Did my TR at Randhem and had a wonderful experience. I would highly recommend them. Yes, there is alot of work involved both prior to your arrival and, of course during the training program. I have to again thank both Mike Randhem, the instructors and mgt at PanAm. All did a fabulous job. Yes, I'm currently employed flying the 737-300/500/700.
PS: I can't speak on the visa issue but I do know that PanAm officials will in fact, NOT, let you into their simulators until there is TSA approval.