Let me guess...posting from a cell phone? Is it that hard to use shift and punctuation on a cell phone?
You need to read the threads in the link because they outline the differences pretty well
http://forums.studentdoctor.net/showthread.php?t=277317
Youre going to need to see which one aligns with your goals/aspirations.
I would imagine peoples reasons for choosing HPSP over FAP for most are the fact that HPSP is immediately seeing the money and support rather than living in debt for 4 years and then getting some relief. Immediate gratification...its the American way. Many people in America sign up for things without the foresight to consider their life in 5-10 years.
For me personally, the cons of HPSP arent really a concern for me. Both my wife and I come from multigenerational AF families and are both very aware of the lifestyle that comes along with service. My mother is currently an AD AF nurse and in addition to her perspective I have met many military doctors and the majority of my medical experience has involved current or former military docs.
Also I am interested in a primary care specialty so I am not too concerned about being stuck in a GMO tour and not getting my residency of choice. On that note, I am aware that I may change my mind and decide to pursue a more competetive specialty. I have met many flight surgeons, both those who hated and enjoyed their GMO tours, and spending a few years at this doesnt worry me.
The financial stability during school is a nice perk too, especially with a family to support.
Youre still a few years from med school so make sure you really investigate military medicine and military life in general before you sign up for the financial perks. Talk with as many active duty docs as possible and not just the ones on SDN or those that the recruiter sends you to.