I have been running these components for over a year now and love them!!! Replaced a set of Infinity Kappas 5X7 (second set) with them. Have an old Kenwood competition amp hooked up to them which is connected to an Alpine head unit. Set of Pioneer 5X7 in rear doors hooked directly to the head unit. 8-inch sub installed in front center console, hooked to old Pioneer competition amp. I took most of the bass out of the components and these things will scream.

Although aftermarket speakers better the sound over the factory speakers, you will never get good quality sound unless you replace the factory head unit.