I use 47mm/80a wheels, but I think the fact that I weigh a lot more than most goalies counteracts the loss of friction
Actually Bernie is dead on. I do tend to slip at times, and I'm about the least-explosive guy you'll find. I also play on a wood floor and on a urethane floor and I prefer both of them far and away over sport court. The floor at Oak Hill was pretty darn grippy too.