FWIW
Would suggest the .357 Maximum and load down. I believe Remington still produces factory ammo and .357 Maximum brass is still pretty easy to get. Any reason why the .360 DW won't work in a Model 40/740? I've shot .357 Mag and .38 Special out of mine. .38 Special from a Model 40 is kinda like a loud .22 lr.
If your thinking maybe the gun would become collectible, I'm here to tell you I accumulate Dan Wessons. None are collectible as far as I know.
Take Care