I am using the 3910 and am very happy with it. I thought you might find the following review helpful:
http://www.hometheaterhifi.com/volume_12_1/denon-dvd-3910-dvd-player-1-2005.html
In this review, the reviewer compares the 3910 to his existing player, the 2900. Plus, in the audio portion of the review (which I found very interesting), you will notice the reviewer uses Axiom speakers...similar to what you are using (M60 vs M80).
While I haven't heard or seen the 2900 in action, I know the 3910 looks and sounds amazing. One last note, while it may not be a big issue in deciding between the two, the 3910 has an HDCD decoder, which the 2900 does not.
I hope this helps.
