I own the Pioneer 535 and the Denon 2910. I have them both hooked up to my system. I use them at the same time, and usually will have a DVD in the 2910 and 535 at the same time, switching between them.
I just bought the 2910 recently (a couple of months ago) to improve things.
My experience is that while there were improvements in picture quality, they do not justify the price difference. DivX support with my Pioneer is much better than the 2910. The 2910 can play MP3 better, but it supprisingly lacks any decent features for MP3 (play lists, repeate ... etc).
I have a dedicated CD player. The quality of the 2910 is not much better than the CD player.
Saying all that, I will still keep the 2910 because of the nice playback features and the picture customisations. However, I still maintain that the quality difference does not justify the price paid.
