I'm quite a newb to Home Theater so bare with me.

I've just bought a Panasonic plasma TV, and inherited 2 Mission 780, and 2 Mission M71 bookshelf speakers. Eventually I plan on using all four of these as my rear array, but for now the 780's will work the front until I can afford some quality floorstanders.

I think I can find a decent center and sub, but I'm really debating over the receiver. I'm considering the Denon AVR-787, the Pioneer VSX-1016, and the Onkyo TX-SR604. Is there a clear winner hear? Some have told me that Denon by far has the best processing of the three, but it doesn't support HDMI. The Pioneer has THXSelect2 certification, but will that matter if it's not as good as the Denon anyway? And the Onkyo appears to be slightly more cost effective than the others. Yet a few others have suggested I switch to Yamaha all together.

Any thoughts?