I've used the Redding 2400 Match Precision Case Trimmer for many years; it has served me very well. I highly recommend it. I also have an RCBS Trim Pro that has served me even longer than the Redding trimmer. I like it very much, especially when paired with the 3-Way Cutter for the various calibres. Used properly, it can be a great time saver.
I just use the very low tech and inexpensive Lee cutter and stud set up. Chuck the shell holder in my cordless drill, load a shell casing, and run it into the cutter. Then chamfer the shell while it's still on the drill. It's fast and works well, but I'm sure not as precise as the above mentioned trimmers, or at least not as adjustable. Shells get trimmed to SAMMI min trim length.