NINe.1, gonna be bout the same wattage as xenon, but a lot cheaper and smaller (one of my biggest reasons, I don't have the room in the truck for a xenon). Ohm stability is nice, and I'm sure the xenon sounds great, but I haven't had any problems finding the correct impedance models for my subs. Either way, you're good (or great). The autotek i haven't heard much about.
EDIT:
NOTE: Jmac knows a lot more than I do, so listening to him might be better.
EDIT:
NOTE: Jmac knows a lot more than I do, so listening to him might be better.