Regarding connecting the Xbox 360 via optical, it looks like the only way to do this is if I use the VGA cable. (Edit, oops, I was wrong. I never even noticed the optical out on the 360 Component cable - that said, is there any advantage to using VGA over component?).

I'd rather not do this because I'll have to run that wire directly to the TV (both DVI inputs will be taken on the 990, and I'm not even sure I could use an adapter for VGA-DVI).

Plus, I don't know how well my TV will handle VGA compared to component.