I tend to knit very tight and have broken a few plastic looms, but I have had no issues with these ones. The looms are very well made and the pegs are exceptionally sturdy. these will be the only looms I use from now on.
Love the looms. I am doing a afghan on the 160 peg loom. I have tons of dish cloth and towel patterns I've been saving. I also have a ton of cotton yarn. I can now use 1 strand of yarn istead of double. Don't care for bulky patterns.