Justin I also agree with Nick that the other software solutions available are equally as viable as Pro Tools. Digi has to keep up with their competition.
I do use Pro Tools at work. But not at home. I totally avoid mixing inside the computer because of all my bad experiences with PT. Instead, I use my multitrack software (not Pro Tools) as a tape deck. The RME Hammerfall card's outputs sound just as nice as Pro Tools, it performs well and reliably, and I never have an issue with it. The DA7's summing buss is more workable for me, it is easy to see what's going on and I like how the result sounds. Best of all - NO DSP CARD NECESSARY. All my processing can be done natively or with the DA7.
Nick - It is mentioned in the Pro Tools 24 Mix Plus manual how it is possible to overload the buss in 16 bit mode without seeing it on the meters, and how that has been corrected in the 24 bit version (which I have not confirmed, actually to the opposite). However, it is possible that it is the plug ins. I will check into that.
Regardless, the PT mix buss issue is really moot if you use the DA7 for one of the things it does best - mixing digital audio.