Have been using these tubes for a few years now, they hold up pretty well. I ride 1,300 mi. a year, mostly on the road, still get one or two flats a season, but that might be in part to well worn tires. They hold air pressure much better than an average tube, I always try to keep one of these on hand, but last year I had a flat and the bike shop put one of their tubes on the front wheel. I noticed after a couple weeks the wheel with the Michelin tube will have 10 lbs. more air in it than the bike shop tube.
It's always a crap shoot when I order new tubes because I don't have to buy them that often. I commuted for years on the stock Bontrager race lite tires that came on my bike. I never changed tubes and I never changed flats. Those tires are TOUGH! But, they are really hard and narrow so I changed to some wider tires this year and the first set of tubes I bought with them were some no-name bike store tubes. The goat-heads made pin-cushions of them in a week! But with these Michelins, I have yet to have a low tire, let alone a flat. I checked the air pressure at least once a day the first week and checked it once a week since then and have not had to add any air. Heavier to be sure, but I needed more training weight anyway ,-)
I have around 200 miles on these tubes at the time of this review. Installation was easy, valve and keeper nut seem of good quality, and so far the ride is great. I run my bike with 70 PSI of air in the tires and over a couple weeks I haven't really lost any PSI of pressure when I put a gauge on.
I run them with tire liners on city streets. (lots of road hazard here) I have not had a flat for 4-5 months. I ride 75 - 85 miles a week .
I would definately recomend this tube.