+2 on SVS SB2000. I have two of them, and together, they greatly reduce subtractive nodes in my room. They go down to 19 Hz, which is low enough for me. With 500 WRMS per sub, there's plenty of clear, note defined, low end grunt.
Subwoofer suggestions
I have a pair of Pioneer S-1ex's , now looking to add a sub. Room size is 12x18 fairly well damped.