If price isn't a real issue, buy a Dillon 650. Caliber conversions are a bit more than the manual index 550 like I use, but it has a 5th station which allows the use of a powder check system that will catch double charges or squibs. You can make a lot of ammo in a short time on a 550 or a 650. For 5 calibers the 650 will cost $2-300 more, but if you can swing it you will be glad you did. I really like my 550, but if I had it to do over I might spring for the 650 if I had the extra money.