Mine wore 1/2 out then stopped wearing.
I have 5000kms on my bike mostly offroad with 13-50 or 13-48 gearing for most of that, I did have 12-50 and 14-50 on it for a bit.
I've gone through the stock chain, 3 front sprockets, 1 rear and two sets of rear brakes just to give you an idea of how hard I am on the bike.
I run the chain just a hair loose.
I compressed the rear suspension until the swingarm was straight back then adjusted the chain until it had 1/2 an inch of slack, this turns out to be between 1 1/2 and 2 inches of slack when the bikes on the side stand. I was shown to adjust chains like this when I was a kid so the chain is never to tight, thats hard on gear...