They're super fast, really. Their size is in no way indicative of their speed. Mine was out the other night (don't ask) and I got a frustrating refresher course regarding their speed. Temperament? I'd say aggressive, not mean. Definitely not for handling that's for sure. The bite's not so bad, bit they do hold on, that makes it frustrating. I've been bitten by worse, that's for sure.
I find when mine bites if i just set him back in his terrarium, he lets go pretty quickly.