I think because of the price range, and the performance of the Auzentech Xplosion. I've read reviews comparing the Auzentech Xplosion and the lower-end of Auzentech, the XMystique
, ~$60 price range with the HT Omega Striker.
HT Omega is a good brand too, but, they don't only offer 2 cards:HT Omega Striker
and HT Omega Claro
thus didn't fall into the midrange card I've been looking for.This guy
was pretty satisfied with it too
And last, I personally would hate to see the limit of my component in a short period of time after I purchased it, so, I would rather pay an extra premium for it.
Hope that helps.