I have a MGM .357 mag barrel.
Someone asked why buy custom over T/C or F.R.O.
Well, my MGM barrel is made the way I wanted it. A faster twist (1:14), a higher quality blank (Shilen), a tighter, smoother chamber with a short throat. It shoots all my handloads well.
My factory .44 Rem Mag is good, no doubt about it, but it leads much more quickly and the chamber is definately sloppier and rougher with a long leade into the rifling.
I think both are good values for the money.