While JL's and Alpines are great, they are also expensive and if that is in your budget, by all means go for it. However, we usually suggest JBL's GT series for those 6.5" door speaks and the pair of 4X6's. You can stay with the coax's to keep labor really simple (just swap em out) or upgrade to the components for a little better staging. You can get all three pairs of coax speakers (GTO627's and GTO 6427 and a JBL Gt amp (GT5-A604) for under $500 installed complete. This is a nice package that we have put in many of the older Burbans and it sounds good w/o breaking the budget. However, the step up is the components in the doors (GTO-607C) but add about another $100. IMHO, it is worth it since the sound staging is much crisper.