I think it is the best subwoofer you can buy for a bookself system.It realy works good with my sisters Aiwa bookself system and if you don't have billions to spend

Controls on front, good sound, excellent value

only three high-pass options, could use more power

This sub is one hell of a bargain. It sounds much more powerful than its specs lead on. I added it to my NSX-V50 Aiwa mini-system and it enhanced the sound quality infinitely. The most noticable difference is audible in classical music and music which does not already have a lot of bass. This subwoofer is excellent at filling in sound frequencies on all songs, and good at providing punch to the bass in rap/rock music. It retailed for $130 when I bought it, but I got the sub half price because it had been opened and immediately returned by another user. I added a service plan and have experienced no problems in the system thus far. My friend has a home theater with a $300, 100-watt Mirage subwoofer and this one sounds a hell of a lot better and more powerful. The controls are very convient and intuitive; many subwoofers I have seen have controls on the back of the unit, which is not nearly as convenient. The subwoofer is also great for watching movies. If you have a home theater, I'd suggest a more powerful subwoofer, as it has to compete with five other speakers as opposed to the two speakers accompanying the subwoofer in my system. I also think this model is better than the one it replaced, so you should grab one if you can find it.