Got an Asus D2X, and at first I thought it was a huge mistake.. Crashes galore and the games that didn't crash, Dawn of War 2 had major bugs - unit speach would slow down but action would stay the same and Battlefield: Project Reality, I had nasty screeching every so often.
Updated the drivers - took a bit of time as the Global download server was full, but once I peered to it it downloaded in seconds and you can download the patch via torrents if preferred.
Loaded DoW and it was perfect no problems. Loaded Project Reality, and was able to set higher settings than before with better clarity.
I have only really noticed Dolby Headphone on Project Reality and it was phenomenal, crawling along hearing pops and hisses above your head, whilst jets come screechign overhead. It was mightily impressive and much better than when I used to use CMSS on my Audigy 2.
Insurgency for HL2, I have played it, but either my settings arn't right or it's jsut so good I don't even notice the virtualisation. But even still it's very nice.
In all honesty I'm not sure which is best in real world, I know on paper the Asus is better than the creative, cheaper too and seem to have less scare stories when it comes to Vista (not to say if you do get one you will have problems as there are people running it fine).