I've noticed diminished feel in Microshift bar ends in 2,000 miles on a bike. Still functional, but not as crisp as they were new. I've come across one very worn out, swapped out the parts inside, and it felt like a brand new shifter. Having an easy to repair shifter is great, but it would be nice if they could also make the internals last longer.

Most of the Shimano bar ends I've found that were dead have been due to crashes rather than getting worn down inside.