Added a couple to an i3 clone with a MKS Gen L board and A4988 drivers. Did a pretty decent job and getting rid of the noise on X, but Y was a little louder than I'd like still. Swapped out for DRV8825's and the difference was night and day. To be sure I disconnected the smoothers and could definitely hear a whine again. Have only done a couple if test prints with them and it's hard to say if they've had a dramatic effect on quality, but I can't hear the printer upstairs anymore so I don't really care.

These are one of the best investments I've ever made to my printer. I really couldn't believe how much a difference these cheap little things make! The prints have never had better surface finishes and the consistency of the printer seems a lot nicer (micro zbanding due to XY slop / overrun). They do get HOT so please make sure you do your wire runs accordingly! Now that I know these are a thing, I would pay 5X what they are asking for them!

Installed on my Tevo Tornado with a Base Gen 1.4 mainboard, helped solve Salmon Skin issues on prints!