Hiya Bray,
I fairly recently got a SVS PB1-ISD. I am completely satisfied. My room is ~14x26 with sloped cathedral ceilings to 18', and opening to a very large, full-height foyer/stair area (10x14x18?). I do not yearn for more sub in any way, and find the HT depth and musicality to be grin-inducing. Service was top-notch, as is the fit and finish. I had several prompt, candid and helpful email exchanges with the folks at SVS; the personal advice I received helped my decision-making and overall satisfaction.
I'd have bought an Axiom sub if they made a down-firing model. Besides the testimonials, a large contributing factor in my choice of SVS over Hsu was my ongoing desire to support American jobs whereever possible.
