Personally, I can't stand the drawbacks. Three abilities provided -Speed. -30% damage, and -65%[?] Recharge from Granite. Seriously?
30-40 mph may seems fine to you, but it's still slow. Your other teammates get ahead and tank for ya. Also, switching between granite and non granite is lame.
Unable to jump ruined the fun, I don't understand why can't we jump? I'm even more confused when the GMs all over PI, The Hive, and the Abyss can jump and normally run, but we, the players, can't? What?
Edit: Just to be clear, I'm not into teleporting, none of my characters have that. Also, I find it a bit silly that we have to waste slots for +run speed. I had Granite/Fire tank back on live. Nowadays? I'll pass.