Its important to note that the entire ASUS line has added EAX5.0 emulation via their drivers, something that wasn't avaliable yet at the time most of the cards reviews were written, which is a major plus.
I prefer the D2 mainly because: 1: Less chance of incompatability (No floppy power connector, no PCI->PCI-E bridge chip) 2: Sererate Optical input, Optical output, line input, and line output ports (VERY few offerings have all 4 of these as seperate ports).
VERY simmilar either way though. The only issue I have with the card is its not in a particular good price, with the D1/DX/Striker almost as good for a cheaper price...
which is better in terms based purely on the sound and its sound quality.
the best of the auzentech or teh D2x?
Very difficult choice but I'd go for the D2X It has better driver support and the sound quality for music is better.