I've started with Lee products, because that is what was I could afford at the time. Most of the stuff worked well, with a few glaring exceptions. As I got older and the boys moved away, I slowly sold off almost all of my Lee Stuff, and now have some Hornady, RCBS, and Redding dies. I still have a Lee C style press in the shed and a Challenger press on the shelf, plus a few of the Lee case trimmers, but what I use is RCBS. I've had to invoke the lifetime warrenty a time or two for o-rings for my bullet sizer, primer tool and a mold and handles.
The last Lee Die I bought was for a .45 Colt, and the shellholder fit nothing that I was trying to load. Lee did send me a replacement within three days of my e-mail, but the I ended up replacing the dies with those from RCBS. The expander didn't want to work well with oversized bullets....