Barber:
I load a large number of .357 Max's a year and have never used anything but Lyman .357 Mag sizing die. The Lyman dies work just fine for .38 specials, .357 Mag, 360 Dan wesson and the .357 Max. The only problem that I had to over come was the seating die was not made to seat Pointed nose bullets. I had a RCBS .357 die set and it had a seating die that worked. By the way I don't think the .357 mag RCBS sizing die would work on the Max, it appears to be shorter that the Lyman.