Help: DVI/ DVD, Nad t-534, Sony 3100 ES, Marantz,

Out of the ones you mention....the 59avi would be a step up from the 2900 for video.
The 5900 would also be better...but unfotunatley it has major macro blocking problems on a lot of different displays.
If you try any cheap player that has the dcdi 2310 chip like the 5900 has...and see macro blocking...then you will see it at least as bad with the 5900.
The 3100 might be worth a try also and has no macro blocking.

cool thanks for tips.. did not know this about the 5900...
Any ideas on Marantz, American Home theater has one new for 589 plus shipping? also: do you recommend other dvd players like the Cambridge Audio 79 ( i think) Spearit sound sells it for 300..
NAD? any others worth considering.
thanks

The only others worth considering imo are 1.k or more...and not found used very often like The Onkyo SP1000.
The Denon 3910 for some reason does not show the Macro blocking as much ...or at all in 720p and should be an inmprovement over the 2900.
The Denon 5910 offers the very best video...bar none.
The Onkyo sp1000 has better audio than the 5910 and almost as good of video and is what I will be using until Blu Ray gets here....but these are 1500.00-2500.00+ street.

As far as your list...
For video the 59avi....for audio the Marantz.
There is the new Pioneer 79avi that supposed to have improved audio for less than 1k street that might compete with Marantz for audio.
The Pioneer has a great rep for quality control if buying used also.

I can't comment on the NAD or Cambridge as I have seen neither and I am not sure exactly how picky you are with video/audio quality.....but I highly doubt either of these would be an improvement for video over the 2900.

If the 2910 did not offer much improvement....the Pioneer 59,79avi,Denon3910/5910 and Onkyo SP1000 surely will....and the Sony 3100 es may also.