I'm not sure which Onkyo model you have, I have an 807 and a 605, there is a long thread about the 807 on this site and all the failures of the HDMI board because of over-heating. I had to send mine to the shop twice before they got it fixed and even then when I got it back the iPod dock no longer worked. I liked my 807 for the features and it was an upgrade for me from the 605, that is until it crapped out and I read about how many others crapped out as well.
While it was away being fixed I picked up a Denon 1912, it was a cheap replacement while my 807 was in the hospital.
Right now my set up has the Denon running and the 807 in a box. It does as good a job as the 807 did for watching tv/movies as I never relied on the 807 to up-convert my video, my Panny Plasma does a fine job without any help from the receiver. I also fell in love with the airplay feature of the Denon.
Oh and yes you can't cook an egg on top of the Denon.