I felt obliged to reply. I used a RCBS RC for years, my main issue was ram/die alignment. I just felt it wasn't right. I bought a Redding Ultra-Mag, the design and workmanship are top drawer. It has the power to do the tough tasks, my issue with it is that I am so used to inserting the case with my left hand, I just find that the arms are in the way. Also bought a RCBS Summit, it really shines for seating bullets. I also bought a used Lyman T-Mag II, it is my go to for 30/30, 38-55, 38/357, 44 Spl/Mag. Other than the primer catcher, it is a good working press. My general duty press is a LEE Classic Cast. After a bit of fiddling it works to my liking. Best of all is all the primers and primer junk goes down the center of the ram and into the plastic tube. The Redding U-M has the same feature, a must have IMO. I don't have a Big Boss II, but IMO it should be a pretty fantastic press. It has all the features that I would want in a press. I've also owned and used a Redding #25, a turret. Redding makes good quality stuff.
My must haves for a press are:
- primer disposal away from the works, out a tube out the bottom.
- linkage that has good mechanical advantage
- Linkage that toggles over center
- decent sized opening
- comfortable handle operation, good ergonomics
After those are met I look at some of the other features, the nice to haves.
BTW, I modified my LEE Classic Cast to toggle over center and closed off the opening for the priming doohickey.
If you compare linkages, the LEE Breech Lock Classic Cast has a better (IMO) linkage geometry, but fails on the primer disposal, (again IMO).