I have the 2900 and it's a great universal player.

It has a good tranport. For red Book CD, i use the digital out to an Audio Alchemy DTI pro32 interpolator/jitter-reducer, DDE V3.0 HDCD D/A and DLC. although the 2900/2910 use 192kHz/24bit DAC's, I like the sound from my old digital processors

I think the 29i0 has HDCD and Denon's ilink, which allow digital transmission of hi-res DVD-A and SAVD to a denon receiver. Apparnetly the 2910 has received stellar reviews for an inexpensive player