I know someone who has a CH4D 10ga sizing die and he just ran through some RMC cases for a friend, it worked fine. We shoot big bore rifle so big dies are not a problem, my Hollywood press takes 7/8" and 1&1/4". The real problem with having RMC turn brass to fit your chambers is that they are 2 years out on orders. That is actually how we ended up with the RMC brass that needed to be sized, it was bought at auction to avoid the wait, in our situation sizing the brass was the right answer.