Bought back in August but only installed in December. Life was busy.
Worked rather well for a few days. Then it began slipping in and out of every fitting I could put on the extruder. Didn't matter whether metal or plastic toothed, or if the coupler was brand new, every retraction would pull it in and out. I tried different sizes of clips. None helped. 3D printed some. Still no help.
It was getting so bad that filament was binding as a result. Something that'd never happened on my stock tubing.
I was going from good quality prints, absolutely 0 stringing when first installed, to out of control stringing.
Tried seeing if I had cut my tubing too long. Nope. Tried seeing if it had just worn out (odd that it would so quickly after install). Nope. Went through the entire length of tubing and 4 couplers trying to diagnose the problem.
Went back to my Ender 3 stock tube. Sitting here right now watching it print like nothing was ever wrong.