I am exactly the same position as you. I have a 42pd5200 and am in the market for a DVI player.
I narrow it down to 2 choices. Either the Samsung HD945 or the Denon 1910. The Samsung has had bad consumer reviews in the US, not so much in the UK. The Denon generally has excellent reviews in the US. In the UK, the reviews for the Denon is generally good but there is some recurrent complaints about macro blocking issues (which seems to affect all Denon models except for the highest end models). The Samsung can be had for around £150-£160 and the Denon about £190-£200. The advantage of the Samsung (apart from price) is that it is a universal player - it plays DVD Audio and SACD. The Denon is not. But overall, from the reviews I have read, I think the Denon is better player. If you get the Denon 2910 (£500), you will also get a universal player. I am also thinking about the Denon 2910 to get the universal player capabilty as my current Yamaha Amp has a 6 channel input - but it is a big jump in terms of price!.
Hope that helps.