Any suggestions for a good small to medium sized sub to go with my Monitor 10s and Cs350? This is for a second HT system and I'm thinking 10" to 12" for no more than $450. I was considering DIY, Polk ebay store (many options), used Velodyne, SVS, HSU, etc. Due to space issues (and if the boss has her way), I may also end up using my Monitor 5s as fronts or maybe some LS 70s (if I can find them). Are there any well regarded "sleeper" subs out there?