i have the Polk Audio Momo 6.5" components in my Probe GT with a Planet Audio 200 X 4 RMS amplifier. Very clean sound with very hard hitting mid-bass drivers.
Also check out Rockford Fosgate Punch Series 6.5" components (P162S). They retail for around $200.00 a set. Here's some pics of what we did in a 1997 Chevrolet truck in custom fiberglass panels....