I've seen some pretty impressive LEGO tire driven/cushioned monorail displays that put miles of wear on the track and the train cars that ride on it.
I'm hoping a monorail expert can tell me (about) how many hours of travel do you get out of the rubber monorail train wheels before you have to replace them?
Do you have to use something to clean the tire marks off the track, or does it wipe away?

These two sizes of tires were used to run Joes train.
...The tread on the driven tire is beginning to wear down.
...and you can see the non-powered wheel has begun to separate.