RE: procharger stage 1 & 2 differences?
If you ever plan on upping the boost on your current head unit or even upgrading the head unit, getting the 3-core intercooler now for a nominal upgrade fee is better than having to buy a whole new intercooler when you need one. It's called scalability.
I think the intercooler that comes with the kit is the only major difference between the two kits.
2000GT - Tri-Ax,MagnaFlow Tru-X/Catback,P-1SC @ 8psi w/3-core IC,King Cobra clutch,MM fullength SFC's: 398 RWHP/411 RWTQ on Mustang Dyno