I have looked at some of the same models. Some of it depends on what you are looking for out of a receiver. Are you looking for just dolby digital/dts....etc?
I would drop the sony out of the list for sure.
The denon is a nice receiver but a little pricey.
I my self have looked at Denon's 1802 an up, Marantz 5200 and up(Marntz have DPL II and circle surround).
I am thinking of going with the outlaw 1050 considering it does have a 30 day trial period. If i don't like it I can return it.

Do you read reviews at http://www.audioreview.com/. That gives you more ideas on what people think!!!!!!!!!