If you want boomy I've been told their is a Dayton for abour $130-$150 that's good. I've been looking at the Velodyne VX-10c for $164 shipped that's supposed to be good but more for Sound Quality but I'm still researching the SQ aspect.
The Daytons aren't considered boomy by most, though they aren't going to be top of the food chain subs either. I'd probably move up to the Sub-100, which is $124 but a 10" and larger amp.
I was thinking up your price a little and go with a JBL venue sub 10 with a 150 watt amp you can get remanufactured on ebay delivered for about $130 I have one hooked to my computer (along with 2 pair of fisher sta-381) if you want to add a little more to the price you can move up to a 12" on ebay too.