I previously was running Rockford Fosgate Punch P-652 components in the front doors of my Xterra with an Alpine amp pushing 45 rms, and the bass response was nonexistent, mids were poor, and highs were fantastic. Sound quality was very good but i wanted something that was a little bit more well rounded.
I was hesitant to switch to a coaxial speaker though, but friends always said great things about Kicker products and since the front doors fit 6x9's i figured it was worth a shot. Wow. I can't even describe how much better these sound than the Fosgate components that cost twice as much. These wont win any SQ competitions, but highs, mids and lows are all clearly defined and I just can't imagine getting more sound for the money. Also, these have the best bass response i have ever heard come out of a coaxial speaker.
If you have a 6x9 opening in your car, i would give these a shot. Prepare to come away impressed.
Pros: Bass response, a lot of bang for the buck
Cons: Highs aren't as crisp as previous components, but that was to be expected.