Security Forces UW (PRP)

Sirs (Marines only), I know this topic has been on here before and I have done the research but there isn't anything really clear. I am a poolee shipping out in 3 weeks, I have just gotten the USMCSF UW (PRP) contract. I would like some info on this MOS, the battalion, FAST or PRP. Basically Sirs, I am looking for Marines that know exactly what it's about and have served in either. I respect all of your valued opinions but I am only interested in the Marines that have been here. I have looked and looked and its very scattered and I would like an ordely answer if any of you can help me I would greatly appreciate it.

Thankyou Marines-thankyou for your service and your help