The AVIA is more complete as far as setting up audio and video although the setup takes a little more time due to the extra detail (at least when I did it).
It doesnt really matter which you use. Both will work equally well.
VE has improper image centering. Avia has inaccurate gray scale (color contaminated) levels. You have to use both when doing a "full service" calibration.
Digital VE is not out yet. I was originally supposed to be out by Oct - Nov of last year. I have seen some of the patterns for this disc and think that they will be of benefit to most people. There will also be a DVHS version of it which I am very much looking forward to.