Eric:
First, you have to take everything here with a heavy dose of perspective. People feel very passionately for or against the military, and military medicine. Galo and ActiveDuty are both experience physicians with the military. Their history on this board has been generally very negative about their experiences with the military. Believe it or not, other people actually have good experiences in the military. They are not generally spending their time trolling medical student bulletin boards. It is good to have people tell you about the negatives, so you can make a decision with your eyes wide open. However, I don't thing anyone going into medicine has any idea about what their practice will be like in the 7-10 years it takes to complete training right now.
That said, the education you will get in whatever medical school you go to has little to do with the school and everything to do with what you put into it. Basically, it is what you make of it. Plain and simple. A big name place is great, but means little when it comes to taking care of the patient right in front of you. Bleeding does not stop when you tell it where you went to school and the pathology doesn't magically go away because you impressed it with your diploma. I work with very good doctors who went to no name schools. A doctors who aren't worth crap who went to big name schools.
I can only speak for my experience at a military residency program and in my specialty. In the past 8 years, only 9 programs in the entire country have had 100% ABS pass rates on first attempt. Of those 9 two are Army programs: BAMC and Walter Reed. Sorry, Tufts, Harvard, MGH, blah blah blah, are not on that list. You can get a good medical education in the military. Again, it is your education and you will get out of it what you put into it.
I also disagree with Cactus. There are many, many entry points into military medicine. They will not turn you away.
My 2 bits, is to choose the path that will afford you the greatest amount of agency and ability to choose. Choose your specialty, location of training, terms of enlistment etc. If you go to USUHS, they have you from square one and you have to play by their rules. HPSP, you have a little more wiggle room, but not much. There are several loan repayment programs where you go to the residency of your choosing, specialty of your choosing and then go through the military to pay back loans and so forth. Keep all the options on your table, the earlier you sign, the more you play by their rules.