We have 110/80, 140/64 mesh that is imaged every 2nd or 3rd business day and have in service dates from Feb 2010 and even a few older than that. 33-34 Newtons on M-3 roller frames, no ink stains, an occasional mesh war wound in a non-critical area which equals hundreds of cycles with about 80 impressions on an average job around here.
So do the math and we have a a crap load of impressions in our screen life cycle, take care of your screens and they take care of you.
My 2 cents....