I'm very impressed, I currently have the GP5000 tubless 28s. I just hit 2002 miles on them without a single flat (now I'm doomed...) I even did a solo double century Friday without any patches or tubes along (I'm brilliant right??), at one point I found I accidentally mapped through around 10 miles of loose, chunky gravel, and rutted fire-road (really Garmin? You didn't warn me of this when I created the route), I had no issues and continued on. I even hit a bump so bad the shock broke my Garmin 820 edge for awhile (on the same ride...), but I never encountered any tubeless "burping" or other issues.