I'd take the PB-10NSd over the Sony.
SheepStar
Uh... yeah, I'd have to agree on that one...
First rule, there's no such thing as "too much subwoofer", so if you have a budget and can afford the high end of it, the best you can afford will provide you with the best performance for your money.
The PB10-NSD would suit you very well in that sized room. I'd also suggest keeping an eye on their
overstock page to see if you can score one for even cheaper.
HSU, Dayton and AV123 should all be able to offer a solid subwoofer in that price range as well. Lastly, if you have any DIY skills & modest tool/power tool collection, the best bang for your buck would be building your own... -TD