not many guns can shoot 357 all day.
i do know the reason the korth and french MR73 were, thus the high price tag.
my studies conclude that a 357 is tested and a limit is established as to how many 357 it can fire before it starts to loosen up or fail.
how does the ruger design fare in this area?
I have had to send only one of my revolvers into Ruger for service. It's a 4" 44 Mag Redhawk, and it went "out of time" after about 15K rounds (and untold thousands of dry fires). I shot primarily 225 Grain LSWGC bullets propelled by 24 grains of Hodgdon's Lil'gun. Ruger replaced the trigger, pawl, ejector, hammer and the barrel & refinished my frame to match the new barrel - all for free.
I have more rounds through some of my GP100's and no signs of timing issues, so I think that the Redhawk was a fluke. It was also my 2nd revolver that I had ever bought. I saw Jeff Quinns Gunblast review of the revolver, and I ordered it that day. I talked to Mr. Quinn over email about it on several occasions and compared notes, so the gun is rather special to me because of that connection.