I'm planning to slowly upgrade my system. Currently, I have a Yamaha RX-V2095 receiver with Polk RTi f/x as main speakers and the old Polk LS f/x as surround speakers with a Polk PSW 650 subwoofer, and no center channel speaker. I also have a very cheap no-name $50 non-progressive scan DVD player that I just use as a transport. Since I'm getting HDTV, I'm probably upgrading my DVD player to a Denon DVD-2200 or something around that level.

I'm planning to upgrade my main speakers, and I have about $800-$900 to spend right now. They must be bookshelf speakers. I use the system 50/50 for Stereo and HT. I'm thinking about the Definitive Tech Power Monitor 500's. What do you think of these speakers? Do you recommend them or something else? Would they be a big improvement over the Polks in both HT and music? This is the first stage in upgrading speakers. Eventually I'll move them to the surround (or back surrounds) and get larger main speakers and a center channel.

Thanks!