I like to buy nice subwoofers that have bad amps and power them with outboard amps in my systems. Then I sell the amps to people that can fix them and replace the amp with a piece of wood and binding posts.
This is a quality 500 watt Class D Amp that could of course be used for the Sub it was designed for, a MKI version, or just about any other sub out there. Once you get it working again. The woofer that this Amp was paired with from the factory read low 6s impedance wise on my meter. This may be very useful for possible custom applications.