i'm a Marine SNFO, finishing up API. i got 12.8 hours, including several xc hours, and several night and both simulated and actual instrument hours in NFO IFS. it's not much, but it'll save you a considerable amount of money on your private.
i'm working on my PPL right now (got SCUBA certifiend during weeks 2,3, and 4 of API, then started on the PPL). it's expensive. flying before IFS isn't gonna get you much except requisite hours, which probably won't be a big help anyway. you'll do it all over again in IFS anyway, so just do the first few flights on the gov't dime, keeping records of everything you do in the bird (not just logbook entries...maneuvers and procedures performed and covered).
then go to either the Navy Flying Club at Pensacola Regional, or Ferguson Field out the back gate of the base where most SNFOs live. (Ferguson's rates are kinda high...$74/hour for a 152. instructor is $25/hour, which is prob about right. you can probably wheel and deal yourself about a 5% discount on both if you pay for 5 hours or more upfront (block time).
also, one of the instructors there is a Tomcat RIO by trade. Really good guy, and good instructor.
i picked Ferguson because of its convenience and because i liked the instructor (i will PM you his contact info if you want). Navy Flying Club is a good deal if you're gonna fly a LOT, but i wouldn't fly enough to make it worthwhile...and it's much further away from my house.