Only issue is that these days 90% of motherboards are designed around dual/tri slot cards. That means there are massive gaps between the cards. I would also bet that it runs very hot, and can make quite a racket.
What we need to see more of is dual slot cards with only one slot full of IOs. That way when you water cool them (like my Fury X) you can run them single slot if mining is your thing. Other than that? I really don't see the point in this card. It's not like you could load a crap load of them up as they would just overheat so it's all a bit pointless really.