UST...never had problem one. Problems above are a result of either the tire or the rim having variances in standards or the wheel was not prepped properly. Other points: not all sealants are created equal (orange seal for me), carrying a spare tube is a good idea in case you experience a large cut but the preferred method is to carry a plug kit (plug it and go - much smaller package than a tube, you don't even have to remove the tire). Having said all of that any puncture or cut you would experience on a tubeless tire you would also experience on a clincher....so either way you will be on the side of the road, the difference is on tubeless you will only be on the side of the road if the puncture or cut was big enough for it not to self seal, and you would be back on the road in under a minute if you use a plug kit. I have noticed punctures that have sealed on my bike only after I got home and was cleaning the bike off. Never even noticed it on the ride. If I was on a clincher I would have had to be breaking my tire levers out and changing a tube. Last thing, ride quality is superior to tubs.