I would have to say that the recoil of the 357 is hard and sharp, whereas the recoil of the 44 is a little harder and rolls much more. I won't say that the 44 is wrist killer, as long as you use good form during firing. My opinion is based on shooting 357's in a S&W 640-1, a model 19 with a 4 inch barrel and Herret's wooden stocks, and a Ruger GP-100 with a six inch barrel. My 44's are a 6 inch S&W model 29 with Pachmayer Presentation stocks and a Ruger Super Redhawk. The difference in recoil can be significant when going down in barrel length.
I started shooting years ago with a Dan Wesson that had an 8 inch barrel, shot a lot of 38 Specials, then Magnums, then I moved down to shooting 6 inch 357's, then the 4 and the 2-1/8 inch barreled 357's. My first experience with 44 Magnum was with a Ruger Blackhawk with a 4-5/8 inch barrel. For years after that, I avoided 44's like the plague. When I decided it was time to move up in calibers, I bought the Super Redhawk because the stocks were very comfortable and the revolver is just plain heavy and soaks up the recoil. Now I am learning with the S&W model 29 and starting with light to middle power loads.
So if you really want a 4 inch model 29, be sure you are very comfortable with full power magnums in your 357, then start with 44 Specials in that model 29 before you unleash those 240 grain Magnum loads.
As far as the nickel finish goes, my model 29 is nickel plated. I clean it with Breakfree CLP and Flitz polish. What really destroys most nickel finishes is the ammonia in many bore solvents. Ammonia reacts with copper jacket fouling and dissolves it, it also will react with the copper plating that is underneath many nickel finishes, dissolving it and allowing nickel to lift and flake. Solvents can also attack the surface of the nickel finish and give it a yellow or cloudy appearance.
