I need some Receiver Advice...Please.

[jasoncarmony]

Okay, so my old HTiB died today. I was pretty much just waiting for it to go out before I bought a new receiver. I really would like to have the Onkyo605. I wish they were still in stores. Anyway. I know the 606 is the newer model, but it's out of my price range right now.

I went to CC tonight and saw two receivers that pricewise, are a good fit. However, I don't know how they will go with my PS3 and Sharp Aquos.

Denon:

Denon 7.1 Dolby and DTS Home Theater Receiver
Model #: DEN AVR788
In store price $250

Onkyo:
Onkyo TX-SR506 7.1 Dolby and DTS Home Theater Receiver
Model #: ONK TXSR506
In store price $299. Online $250

Will I be able to get HD sound out of either of these. I believe they have passthrough HDMI, but I'm not sure exactly what that all means. The rep told me to run my PS3 to my TV with one optical cable to the receiver. That way I get everything from the TV coming through the receiver...audio wise.

I am also watching an auction on Ebay for an Onkyo 605.

Any advice would be greatly appreciated.