The only thing to watch for erak is those stand-up targets (access jet bumpers on left, and light mneumonic recovery on the right). The switches might get worn. I know mine had a broken stand-up target when I got it. Thats the only thing I can think of.
The glove itself is quite sturdy, and if its working now, there isn't anything to worry about (there is a nut back there the glove travels on....which is the reason why gloves on route JM's don't work...because that nut is missing or worn out).
I love my JM pin. Everytime I get Rudy from Funhouse to come on during "Frenzy" mode....possibly also activate Yakuza strike (which is inspired by the consecutive "cross shots" from T2 pinball)....my blood gets pumping.
If you wanna see how fast JM is....don't do any drop catches. Hit the ball straight across when it comes down to the flipper. The ball will accelerate so fast around those loops, that you will either lose track of the ball with your eye....or the actual software will have to catch up to the switches hit in the process. Its pretty wild.