That's a nice amp. I think I just might have to purchase one for my Ranger to replace an aging MTX amp which is a tad underpowered for my application.
As for anything beyond 2-way coaxials is a gimmick. You're probably better off finding some 2-way coaxials with an external crossover. Off the top of my head, Crystal and Infinity both make some good 6x8's with external crossovers.
BTW, forget about replacing the rear speakers. You won't notice a difference.
