They were quite durable, we did a large room as our first spray project and were pleasantly surprised at how well these held up. We only needed to use 2, one did sprout a leak about 75% of the way through the project – and we only used one color (white) so we were hoping to get through one 2 day use with one flexliner. No such luck. That said we were gently squeezing the liner to get the most per cup fill after we got the hang of the sprayer. That’s another whole deal… but I”m so pleased we went with the Graco unit other than the more common DIY user brand. We read dozens, if not hundreds of reviews on sprayer units before going with the more expensive Graco TrueCoat 360 VSP unit. No regrets there…
IF you have a Graco paint sprayer that uses these – stick with the brand name