I use them on all my bikes.
I brought along the rebuild kit on this tour, but have yet to use it. The bearing on the right pedal are getting a little loose, but not worth swapping yet. I've ~11000Km on them this tour, plus ?5/6000Km prior. Pretty darned good IMO. Particulalry given the conditions I've ridden through: rain, dust, snow, mud, sand all the goodies which can trash bearings.
I have swapped out my cleats on this tour, but that's reasonable given the distance cycled as well as the amount of walking about I've done.
Mine are the non-platform version eggbeaters. These definitely limit ones footwear to a stiff soled cleated shoe. I 've mostly used my Shimano sandals, which now seem about to fall apart. The soles are still pretty stiff (there's a thick plate in them). I'm lugging around a pair of MTB shoes I bought in Bangkok should my sandals fail.
~Cheers from Hoi An Vietnam!~