Works well, easy solution
Crutchfield Customer Review (What's this?)
Definitely makes a significant difference. Driving JL C2 690tx (which were asleep with the aftermarket Pioneer HU) and JL C2 350x which were fine without an amp. Was able to fit it behind the stereo
Pros: Big difference in sound, works well powered from headunit power line. Easy solution if you don't want the hassle of installing an amp. Very happy with the sound.
Cons: Pricey for what it is, you are basically paying for convenience which is fine. The version that works with alpine headunits is cheaper