For $400 I'd pass it up without question. But shipped (and 2 day free shipping) for under $180 it's a great upgrade! Heck that's cheaper than the front Polk speakers I did, and it will be easier to install as well!

Who here knows how much/what will be involved in wiring it to the factory head unit? Which from the factory stereo should I use for a signal wire to the sub, what gauge wire should I use for power? Any tips?