I haven't used this very often but it seems to be of very good quality and the R8 fits like a glove. This is much more efficient than removing the drawbar for each tool change. Updated 4/22/20. Now I use this set a lot and it still works great! I noticed a review that said "clamping nut was not machined properly", but I think he may not fully understand how to use the item properly.The hole in the ring should not be centered as shown in his picture.You must click the collet into this part before inserting the end mill into the collet. The ring is machined to fit into a groove on the collet and removing the thread pulls the collet out of the taper.You can't just install a collet and screw it together.Hope that helps.