My preference has always been to use Kicker speakers and MTX amps (well since the THunder series Amps came out around '96). IN my Z28 I had 2 sets of Kicker 6 1/2" w 1" tweeter components runnign off a keenwood headunit with built in Sirius. In the back I used an MTX 10" powered enclosure. Sounded really good, but not too loud.
Now, other good Spreaker Brands for components are MB Quart, Alpine, MTX, Infinity. TO be honest, all most all 6-1/2s will give you good mid bass if you run them off a good Amp, its the harshness of the tweeter that seperates them.
2006 Mustang GT in Torch Red
C&L Intake, Evolution Performance Tune, Borla Axle Backs, Hurst Shifter, 4.10's, JBA Long Tubes, Prothane Engine Mounts, Steeda UDPs, FRPP Charge Motion Delete Plates
84 Bronco, 302 C6 on 32 10.50's