I luckily have not had one in for repair but I've heard about the above said problems with diff kinds of the QR pins/inserts.
I just never really got the point of them.......IMOP QR joints are the worst hitting of them all, but for arguments sake lets just say that a good hit is of course up to the individual using said cuestick to decide.........
what I don't get is why they even came up with or had a need to produce such a thing? I can see how its beneficial in a jump cue for sure as you can take it out and put it up super quick........but unless you have 5 shafts

; one for breaking, one for jumping, one for banks, cuts, straight ins then I just don't see the point of having a QR joint on my playing cue?
I liken this to those dam Norelco Electric Razors that have a pack of lotion/shave cream in it.......so when you start shaving you can just push the button and PHHUUUUTTTT it $hits on your face applying the shaving cream.
Like I wish I had a more expediant way to put on shaving cream on my face, and secondly I wish I had a cuestick that didn't take up so much time in my busy day to put together.......
I don't know which was a worse idea but if these things bother you; applying your shave cream by hand or threading a meucci together then you should just give up now before your head explodes from the sheer mental involvement it takes for our routinely simple and quick everyday task......
what are we saving here 10seconds of our lives lol...........i dunno maybe I'm the kook but to me these things are just plain silly and goofey
you want to make something quick for a change go start with the speed of the DMV
-Grey Ghost-