I agree it's less bloated. However, performance isn't as good as newer versions (you need a better spec GPU for 7.3) and the image quality is not as good as version 9 onwards from my experience. Not as sharp. The standalone player wins out in pretty much every regard. Time to sell my HD-DVDs I think.
On my old PC there was only one bluray that gave me problems (using a 8800 GTX and E6850 @ 3GHz), and that was Avatar. There were places it would stutter and choke. I reported this to Cyberlink but they weren't of any help. I also tried PDVD10 and it was no better at all, so it had exactly the same performance problems in the same places. A shame because I would have upgraded if it had worked since I was looking for the added 3D support.
I did a trial installation of Arcsoft TMT and this played back Avatar on the same hardware flawlessly. Since upgrading my PC with a better CPU and GPU, I don't get issues with PDVD either, but the version of the software was not improving matters when I tried it and Cyberlink's support couldn't even suggest that it would have helped either, they acknowledged the problem regardless and had no solutions, just passed the info to their devs and that was it.
I also couldn't tell you (and this is in 1080p on a 52" screen) that there are any noticable picture quality issues in any of these software vendors/combinations - and I was looking for them at the time to see if that would account for WHY the playback was suffering/choppy - so I feel all versions of PDVD are of comparable performance and quality.
Part of the reason for having good picture quality throughout may be due to making sure that I used my graphics card's (purevideo) and TV's picture quality controls rather than relying on PDVD's (though turning these off didn't stop the choppy behaviour with Avatar either, I think that was pure decoding power).
These things aside, when used in conjunction with AnyDVD I'm quite happy to stick with PDVD7.3 ultra for my regular bluray and hddvd viewing, it's just for 3D titles I need something else now, and if I go with Arcsoft TMT then I can have it installed side-by-side with PDVD so I can play every format.