Like several of those who have commented, I use my M.E.C. strictly for bullet seating. I have relegated my trusty "Chucker to prep duties. Yes, there is some debris from every case prepped, mostly primer residue. My 'Chucker is a vintage early '70's so it does not have the new paint which is more easily cleaned. Yes, I believe the M.E.C. produces finished rounds with significantly less run-out issues. Before I got it, I spent hours "tweaking" my rounds to have less than .002' of run-out. Now for a box of 50, OI may "elect" to tweak 1 or 2 into submission. My good wife found a cloth blender cover that keeps the M.E.C. clean as the day I first unboxed it. As far as priming, I prefer hand priming s, o I can feel the seating. One day I may finally retire my "'Chucker" for a coax press but at age, the 'Chucker will probably outlive me. I also like the ability to load long rounds, lime my 338 LM.