Re: Denon AVR3808CI
I'm with Moose, skip the Oppo and put that cash towards a Blu-ray or HD DVD player.
I'm with Dave M on this, I could care less if the THX logo is there if the unit sounds good. DO NOT get hung up in specs such as THD!! The 0.09% you quote is inaudible, and specs are always a little speculative if you know what I mean. As for the IEEE (Firewire) port, if you plan to use something that will use it it will matter. Case in point, some SACD players can output the signal via firewire, if you don't have such a player, it won't matter to you so would be unnecessary.
Which is more reliable? All of these companies are pretty good, that said if you get one that goes bad, you got a bad one and I think each company is equally likely to have a failure so I don't really see this as an issue.
I have owned most of these brands, Denon, Marantz, and Pioneer Elite. All are good. Given your gear, you will need something that can handle all your sources.
I assume the Tivo/Satelite are going to be a single input to the receiver. That said, you'll need four HDMI in's (PS3, Blu-ray, HD DVD, Sat) and one out, three if you are counting you PS3 as your Blu-ray player or possibly five if not and your DVD player uses HDMI).
Since you have HD DVD and Blu-ray, you'll want all the cool new audio formats, and I think the receivers you've listed all do these so you'll be good there, now go out and find as many as you can in your area and listen to them! Pick which one has all the features you need and sounds (and often time looks)_ best to you!
Ken Taraszka, MD