I bought RCBS dies for my 454 for the same reason you did. They were the dies that Freedom Arms sells on their website so I thought why not go with what works for the parent company of the cartridge. If I recall, mine size the full length of the case down to where the case wall meets the web of the case head. I have had no problem with mine.
I have a set of Lee dies for my 45 colt and now for 480 Ruger. I like Docs comment about the "Rodney Dangerfield" of reloading dies! haha I like my Lee dies. In some small ways I like them better than the RCBS because they tend not to loosen up while in a loading session because of the o-ring locking ring. That being said, I am still sticking with the RCBS for the 454. I use a Lee Classic Turret Press and lee shell holder with mine, no problems
"If you are going to go through all the trouble to put a hole in something, why not make it a big one?"