what you really want is Dendix or ideally Snowflex! coming from Ireland, this is the best stuff we have, but thanks to global warming we've been getting a few weeks of snow lately!
Dendix is known for its finger-breaking goodness due to its diamond shaped design but it has better grip for carving.
Snowflex is my artificial slope material of choice as its more cuddley when you land on it, it doesnt have any holes in it to catch fingers and is overall miles better for freestyle, yet it is easier to lose an edge n slide out.
Both of them need to be lubricated, and every artifical slope in ireland and the uk use sprinkler systems that work just fine!
Anyways heres the wiki for it n if you're interested a video! At the London Freeze festival a year or two ago, loads of the american pro riders were freaked out by a snowflex drop in for the booter but the uk riders were stomping it!
Dry ski slope - Wikipedia, the free encyclopedia
YouTube - iPhone Fisheye Lens UK dry slope snowboarding
YouTube - Westbeach Snowflex Freestyle Series 2010 Aberdeen - Snowboarding