I'll do my best! For perspective, I lived with a few UM med students last year, and my job involved working with UM students and doctors almost daily. I grew up in Gainesville, and am related to several UF COM faculty members.
UM: One of the biggest pluses from my perspective is that the students are genuinely happy here! I'm pretty close friends with many many UM students, and though they certainly work hard, I can't think of a single one who doesn't have at least some free time even WITH research and other extracurriculars. They pretty much all seem happy and relaxed, and have nothing but good things to say about the school (keep in mind this is all 1st and 2nd years-I don't know as much about 3rd and 4th.) I haven't heard any complaints about the professors. It's in Miami, which is either a huge plus or a huge minus depending on the person. Regardless of how you feel about the city, though, it's a fascinating place to be involved in medicine! It has an incredibly diverse population which leads to lots of different opportunities for the types of things you'll see and the types of patients you'll interact with. Really, that aspect is awesome! Of course, Miami is freaking EXPENSIVE. You will be paying more, which kind of sucks. It's a well-established program, which is good in the sense that it's been heavily tested and bad in the sense that there's less room for involvement and making changes.
UF: As you alluded to, prior to the P/F change and the curriculum reform, UF certainly had a reputation for unhappy, cut throat students. However, UF is completely different from what it was even 3 years ago. New Dean of the college, Dean of Admissions, and faculty backing them. Let me tell you, I have been absolutely floored by the empathy, kindness, and dedication to improving both UF and the healthcare field in general they've shown. Most schools say they "look at the whole applicant" and "only want kind people," but UF is the only school I've encountered so far who truly has been backing that up, at least this application cycle. Not only that, but they've by far been the most responsive, kind, and welcoming staff I've dealt with, and from what I've heard from most of the new faculty members in power, it's not a fluke of the admissions office. They're making huge changes for the better, and I'm so excited about the direction this school is going! From what I've heard from current 1st and 2nd years, the P/F system pretty much destroyed that nasty cut-throat attitude, and those two classes have been described as being "extremely supportive and close-knit." I suppose one of the major concerns many people have is the new curriculum, since it's very up in the air. On one hand, we'll be guinea pigs, so I can understand the worry. On the other hand, the class of 2016 will be in a unique position to have tremendous input into the future of medical education of this school, which personally, I think is pretty neat. Though I completely understand the worry and there will be some bumps, I think that based on the long-standing quality of UF, the students going through the new curriculum will be fine.
WOW, I wrote too much! I adore both schools, and I don't think you can really make a bad choice. If you have any questions or want to talk more, PM me! I can offer more specific examples and opinions if you'd like. Good luck, and congrats!