Congrats on your new toy T...
As far as the disc, I don't have either. But I did mine with the Sound and Vision/Ovation and it was adequate for me. The Avia has been around for awhile now and seems to be well liked by those who use it. The "Digital" Home Theater is new and is supposed to have some advancements over the original analog version. I'd go with the new one if it's available to you although either will do you justice.
Here's a couple of other sources for tweaking your toy...
http://www.panny.tv/
http://www.keohi.com/keohihdtv/brand...onic_tips.html
I used these sites to gain access to the service menu to set the coarse and fine convergence. WOW, what a difference it made on my set!!! Over the next year or so, you'll also experience what's referred to as the "Evil Pop" where one of your projectors will freak out and go into hyperdrive... producing too much color. Brett explains this and the fix if your out of warranty. Mine happened with the blue projector after about 6mths and was a breeze to fix after I got over the initial fear.
I would also recommend that if your going to do much tweaking in the service manual, WRITE EVERYTHING DOWN BEFORE YOU MAKE ANY CHANGES!!! It would also be advisible to get a service manual from Panasonic(only $10-$15US I think) for discriptions on the adjustable controls and what they do.
If your a Sci Fi fan, I would recommend the DVD "Lost in Space" for a good reference to judge your pictures detail and color.
Enjoy!