I always try to run 50+ in our 800 Burb. Factory calls for 50 front, 80 rear iirc. While the tires do wear fine at lower psi, they do certainly wear faster.
I can say with certainty though that if the ball joints are even a little bit worn, front tire wear tends to get very choppy. Especially if it's a cheap and narrow M/T tire with a soft compound. A good quality tire seems to wear better under the same circumstances.