I know there's a couple schools of thought on this topic (go straight to P school or get some street time first). Most of the medics I've asked, including those on my service's command staff who have an active interest in having more EMT-Ps on trucks, told me that, generally, people who get some street time in before going to p school tend to understand the materiel they're presented with better. I'm sure I could get thru it if I started immediately, but my attitude with my Basic course, and the attitude I'll take into P school is: I'm not here to pass the class, or pass NREMT. While those things are necessary, my chief goal is to learn as much as I can in order to become a more competent provider. Or, phrased another way, to do everything I can to minimize the risk of killing / unnecessarily harming my patients while I gain the experience necessary to become a competent practitioner.