Have a glock factory 3.5 in my 27 and put in a Ghost drop-in 3.5 in my 22 yesterday. A noticeable difference for sure over the factory 5.5. I even switched them back to the factory after trying them to see if I could "really" tell a difference and I have to say yes. Alot smoother pull and break with the Ghost. I could be using the wrong terminology here, but I still have some "creep", feel in the triggers before they break that I would like to correct and make smoother and less travel. Thats just my preference and understand that everybody doesnt want them that way. Im taking the Glock Armorers course on the 23rd here in Houston so hope to learn a little more about them.