I don't have a true DVD-A player, so haven't compared DVD-A vs the DD 5.1 compatibility track included on DVD-As.
However I do have SACD, and in general the DD 5.1 track on quality re-mixed DVD-As sound just as good (to my ears) as a true multichannel SACD. I'd assume it'd be similar with a DVD-A.
With a quality Axiom surround system, the difference in engineering and mixing quality between various albums becomes huge.
The Rumours and Hotel California DVD-As are two of the best, in terms of engineering and mixing (and I've only heard the DD 5.1 version). I strongly recommend them. They are real masterpieces -- the surround isn't artificial or contrived, yet greatly contributes to the experience. Even if you don't like the music itself, it's impressive.
By contrast I have DVD-As of Neil Young - Harvest and REM - Greatest Hits, and the DD 5.1 multichannel mix isn't that good -- it's flat and lifeless.
Although the lack of player/receiver digital connections is a little hassle, it's not that bad. Newer players have some form of bass management. I wouldn't let that put me off. The real issue is whether there's enough quality multichannel material to make it worthwhile. In my case the answer is yes.
If you have good 5.1 speaker system, a big stereo collection, and no PLII or Logic 7, getting a receiver with PLII or L7 would be a good step.
