These tubes are so worth it. They are very high quality and you can see it when installing. I have never had the mysterious seam split or valve breakage like some other brands. There is just one small item after using dozens of these tubes. No, i am not fully on the tubeless bandwagon! About every fourth tube has a loose valve core. Not fully loose but enough to let the air out in about 1-2 days. A quarter turn of a valve core wrench fixes the problem, but it is annoying. I am learned to check the valve cores with each tube change.
I went from a regular valve to the Presta valve and overall the tubes have performed beautifully. They were easy to install and they have held air better than my last tubes.
Replaced a set of tubes when I put on new tires and am noticing that at pre-ride check, I have to top off with less air than the prior tubes. The valve feels very sturdy, too. So far, so good!
These are bike tubes. They hold air well as a bike tube should. Only adding air every few weeks. One tube had a big hole right out of the box which was a major disappointment but BikeTiresDirect sent me a free replacement and now I'm good to go. Fortunately I was buying two only to have a spare so I was able to ride until the replacement came. I can only hope the bad tube was an anomoly.