Couple of questions:
- What's the last dimension on your room size? I see 10' wide, 15' celing, but no length. Also, is this a closed off room, or is it open to other areas like a kitchen/dining room or hallways?
- What made you choose one of the NR series Marantz receivers? Is equipment space at a premium? They seem like good models, but I feel they are better suited where you don't have a lot of space, like a bedroom.
- What sort of budget are you looking at in total. And would said budget be just for a receiver/speakers/sub, or other things as well, like a Blu-Ray player? I'm guessing your HTPC will handle most of that, but thought I still should ask if there's any additional pieces you might think you need.
I think you did alright on the receiver(s), though their might be some bargains in fuller sized models if that would work. Not as enthusiastic about the speaker setup though. 500-600 is a bit low for a 5.1 channel setup IMO, especially if you're paying about the same for a receiver.
Denon AVR-4311CI, Ascend Acoustics Sierra-1 L/C/R, Infinity P362 Surrounds, Seaton Submersive HP, Oppo BDP-93