I have a couple questions regarding the SVS 20-39-PC sub, and I know there are tons of owners out there to answer my questions. 1) As far as placement, do they need to be out in open space or can they be placed behind a chair or recliner in the corner of the room 2) I'm considering two units. I know SVS recommends placing two sise by side, but It's not possible in my listening room. Does anyone have two 20-39's in opposite corners ? What are the results (again,both would be behind chairs) 3)Does anyone have experience with the SVS in a head to head demo with the Sunfire True Sub Signature ?