First off, these speakers are very well built. The first thing I noticed was how large the magnet was, compared to the stock speakers. The stock speakers actually had more travel (i.e. larger voice coil), but they just didn't have the magnet power to effectively produce the low notes, especially at high volume. Getting the speakers in was not too bad, I didn't have any major issues. Just to show how strong the magnet is, when I pulled the stock speakers out they latched onto the metal of the door frame, and it was fairly easy to pull off, but with the Kicker's it took two hand and quite a bit more force to remove the speaker from the metal. These speakers definitely kick. They don't have the low-low rumbling bass of a sub, or of a well ported 8 inch speaker, but with the speaker baffles in place, they provide more than enough bass, and they accurately reproduce the low frequencies. If you looking for the kind of bass that rattles your car, get a sub. My only complaint about these speakers is the amount of treble produced. On my system I really have to crank back the treble, and these speakers don't have the voice coil size to reproduce enough bass to counteract it. All in all, these are great speakers, very loud-due to the high sensitivity, so a standard head unit is more than sufficient. If you want a sub these speaker are also great, can reproduce enough high range to match the most bass heavy systems. I would definitely recommend these speakers.
Pros: Loud, very clear and crisp highs and deep lows, would definitely recommend speaker baffles (gives you a more focused bass)
Cons: High range can be too much at times, average voice coil size