What will you be using it for. Music or movies. The Sunfires are nice for movies, but don't cut it for music. They are just too slow. The REL's work great with both. The Q108E that Tgrisham suggested is a great choice. The wife will love the look, and you will love the sound.
Sunfire, Paradigm or Velodyne
OK, i think i've narrowed it down to three subs and now i need some input. All are in the same ball park as far as price, so before i kick down some dough, thought i would pick your brains. 1) Sunfire Solitaire 12; 2) Velodyne SPL1200 II; 3) Paradim Seismic 12. Room size is 13' x 17'(actually where the carpet ends, but opens into the kitchen and dining room) and ceilings are 8'. I chose these for their small size which is important for the WAF. If i'm missing a small but powerful sub that you think i should consider, i'm always open.