Excellent sub, still in service 21 years after production.
I use it for music enhancement on my Luxman R-117 with many different speakers.
I've had it for about 3 years after getting it in a somewhat cosmetic abused condition. $35.
I am amazed the amplifier is still good, I help out at an audio repair store and the number of less then 10 year subs that the amp is blown or bad caps (humming) is stunning.
If you stumble on one at a good price, working, give it a try.