About 2 years ago I bought a delta 17-959l drill press for my new shop, this was after I had a steel city 17" at my old shop and a delta 17-950 previous to that. The cheap delta got returned a couple months after I got it because of quill slop, then I got the steel city because of the split head casting. I was going to get another steel city for the new shop but at the time there were rumors about them going under and I didn't want an issue and have no warranty support. So after looking at reviews and getting recommendations I got the 17-959l from a local dealer. It is a nice machine and had a tight quill when I bought it, but recently it seemed that the quill started getting loose. I took it apart and saw how rough the machining was in the quill support holes and I believe that is what caused the slop. The high spots wore down and that gave me the slop. So today I implemented plan b.
Now the quill is nice and snug, no slop at all.