I'm looking to get a subwoofer and I'm after some recommendations: I'm looking at a smallish sub for a room 3m x 6m. I was thinking of a B&W ASW610 or BK XLS200/XLS300 or Rel T1 also looked at the B&W PV1 but I think its a little too pricy!! would like to stick to around £500. greatful for any recommendation or feedback from owners???