I bought one of those cards manufactured by Asus and I couldnt see any benefit. The software demos that came with it lacked graphics and I wasnt impressed.
I think its still a bit early for the benefit for that technology but it may be coming around once software takes advantage of what it could have to offer. I read in certain cases benchmarks was lower after installing a physics card than without it. I think it basically was a bandwidth issue with the data transfer to and from the physics card or something to that degree...