I had been loading 38s on a dillion 550 up untill about a month ago. My son needed one so it was given to him and grand kids. I had to dig out old dies which had not been used in over 20 years and one move ago. It was a hodge poge of dies. Don't know how but I ended up with 3 carbide sizers but only one seater die--a lee. The first batch I was unable to get a roll crimp and had trouble chambering the rounds. I have since purchased a taper crimp die but still want a seater die that will give a good roll crimp. I know all should if adjusted right but if I am going to spend the money, I want to get a good one. Need recommendations from serious shooters and figured this was the place to find them.