Oh alright. Well seriously, I think you would get better performace from an Adire Audio Rava or perhaps something from HSU. It would run you just $50 overboard. The Rava uses a very nice 12" driver, very popular with DIY builders.
I'm uncertain of the prices from J&R, but I've seen the S120P II consistently under $400 on eBay. At that price, it's very hard to beat. Yes you can get better subs if you spend more money, but of course the more you spend the farther you are from an equal comparison.
The S120P II received favorable reviews, and my personal experience hearing a few is that they compete at the top of their market segment. I'd get one in a heartbeat, except I've already paid a lot more for the subs I have.