I sat on the fence for numerous weeks trying to decide among the 2900, 5900, 3910 and 59avi. I read alot but today I went to my dealer and listened to them all. Yes....I said LISTENED. I'm as much worried about audio as video. All listening was done into the same receiver, at the same time, using basic 2-channel, analog connections.
I plan on running 480i for now but will upgrade to an SDI solution in the next few months. (Using a Lumagen Vision right now.) For anyone in a similar situation, I offer these comments.
The 2900 is one heck of a player for $700. The audio wasn't quite as good as the 5900 or 3910, but at half the price(of the 5900), its a great deal. The 39/59 deliver better separation and depth as well as a more lifelike presentation. They just sounded smoother, less compressed and overall better.
The 5900 and 3910 are so close, that I had an extremely difficult time telling the difference. 95% of the time, I'd say they're equal. Additionally, the 3910 has superior bass management capability over the 2900. For me, they were close enough that the cost difference of the 5900 wasn't worth it.
The 59avi, as much as I wanted to like it, didn't measure up in the audio department. It sounded thin compared to the others. That's the best way I can explain it. Not bad, but when you heard them side by side, it was easy for me to pick which I liked best.
The verdict (for me)................3910!
It gives you almost equal audio performance of the 5900, firewire input for future hi-res audio (which the 2900 lacks) and arguable better resale value than any of the others. The kicker....it was $300 cheaper than a 5900 and only $300 more than a 2900. Seemed like I was spending a little more to get a player that is certainly the equal(roughly) of the 5900 with alot more future potential than the 2900.
Of course, I'm crossing my fingers that the 480i will be outstanding from the 3910 and SDI will take it to a whole new level. My toes are crossed that the layer change won't be terrible and/or Denon might come up with a fix for it.
Remember, this is what I HEARD. Your results might be different based on any number of factors. This experiment was pretty well controlled and the person with me had the exact same conclusions.
Thanks to everyone for providing their insight in all of these threads!