I participated in the program in '06. I actually had no prior science experience (was an english major in college), so I was at a disadvantage because I was the one who knew nothing about anything, as opposed to everyone else in the program who were seniors in hard science majors. Sorry, just venting...
Moving on - I found pros and cons. The program is supposedly really hard to get into, so I was really excited when I found out I made it. The experience itself did not live up to those expectations. I may be the exception - I was put in the pediatric surgery program, where we were not assigned a specific "mentor" (attending surgeon) during our time. Everyone else (Ben Taub, Methodist, etc.) was assigned to a specific surgeon that they worked with almost exclusively. This was good for me, because I got to work with a lot of surgeons..but bad, because I didn't get to work with any of them enough to get involved in anything really important - some people at other hospitals did research, etc. On the plus side, you get an all-access pass to go wherever you want - you go on rounds with the residents and fellows, watch surgeries, etc. You can go as much or as little as you want (at least at Texas Children's, where you're not assigned to a specific surgeon and no one seems to really notice you're not there - but I probably averaged 7-10 hours a day or so, sometimes more if there was a cool surgery. I also stayed for night call a few times. Overall, I'd say I got around 400 hours over the 10 weeks.)
My first fellow was great, but he left halfway through the program, and I got a new one. I can't blame her, 'cause she was starting a new, very difficult job, but it made it hard for us in the program to get a good experience when she showed up. Also, those at other places (especially Ben Taub, which is the county general hospital) got to actually do some real, actual work in the OR, while at Texas Children's we got to stand in the back and watch - I probably only scrubbed in on 5 or so surgeries or so the whole 2 months.
Overall, I'd say it was a good, not great, experience. If I had been in another surgery service, it might have been much different - I don't know. I did learn A LOT about surgery and medicine in general, and got to see first-hand what it's like to be a resident - so I'd recommed it, if you're interested.
Sorry about the length of this post, but I wanted to share the whole experience. If you have any other questions, just PM me.