I had a Magura on my RM250. It was nice. I bought it to help get an easier pull for hare scramble racing. It surprisingly didn't help it much.
Pros: Adjustable reach. No clutch cable drag or notchyness when it's dry. Hardly any maintenance.
Con: Short lever throw - it would make my already draggy clutch more prone to drag when the bike was in gear.
I just removed it recently and went back to a cable setup for more adjustability and that longer lever throw.