I'm not that knowledgeable in sound cards but the only thing i see in them is the EAX support thingy that many games tend to use like for eg San Andreas and there are more new ones that has it.
Now According to it only the first one has it(EAX 1.0, 2.0). And there are sound cards like from creative that i like more.
Like
Creative Sound Blaster X-Fi Titanium Fatal1ty has EAX 5.0. These cards come with dedicated XRAM(sound RAM you can say upto 64 MB)So it's a thing to be looked into.
So look for those imo
EAX HD stuff and all that.
And from what i know who use Sennheiser HD 555 i haven't heard any complaints about it and people here on TWC that have them simply love

it.
Hope this helps.
