3910 or 2910 and scaling HDTV

Hi all. I've been lurking here for several months, and I just saw the DVDO/JVB power buy that went up this week. I'm very close to buying one of these combos, but I have a few newbie questions.


I'm curious to know what the major differences are between the Denon 2910 and 3910. Denon's website listings make it difficult to read and to do a side by side comparison. I'm most interested in video performance, and I don't own any DVD-A or SACD material.


I'm also a little confused about whether an HD or an HD+ would be more appropriate for my needs. I'm getting an HD signal from my cable company, and whenever I'm watching an HD program, the TV says it's displaying at 1080i/60 (I can't recall ever seeing it say 720p). I understand that either model iScan will process an SD signal and that the HD+ will process HD material as well. My question is if I'm already getting 1080i and my plasma TV can't display 1080p will an HD+ do anything or should I just stick to an HD?


Next, I've been trying to figure out my plasma's native resolution. The user's manual states 852 (horizontal) x 1024 (vertical), but I can't seem to find this resolution anywhere. Almost every resolution listing I've ever seen has the larger number first. Should I just flip the numbers?


Last, my HDTV is a Sony KE-32TS2U. I've surmised that most people use these scalers with projectors and larger displays. Since my screen is only 32" (I hope to get a 50" later), will I even be able to see any improvement?


I've learned a lot over the part few months by reading many posts, and I hope you can shed some light on my questions. Thanks.