600km on first KMC chain-probably would've gone longer but thought I'd swap it whilst everything still new-ish. Replaced that with a BBB e-powerline chain (RM is 124 link so limited options), which is knackered after 500km. This time trying an XT 12 spd sil-tec, mainly because it's not too pricey and 126 links. SLX cassette holding up well. Thinking of changing to a 1 x 10 with an 11-42 cassette next time.
I don't race up hills in Ludicrous mode and am very vigilant with my shifting. I also clean and lube the drivetrain every other day.