I appreciate the input, varied opinions based on actual experience is informative. The rifle that I am considering having built would be strictly utilitarian, "a hunter's rifle for a Hunter" you can say. Since I live here in Alaska and am planning on having the rifle built for moose, bear, bison and walrus hunting it needs to be able to handle Alaska's weather conditions (snow, rain, sleet, mist, etc.) and rough terrain.
To start with I would have the action worked on to improve function and reliability. I would then have a stainless steel barrel installed, contour: a # 4 if I went with a caliber in 375, a # 5 if I went with a 416, barrel length will be 22 inches. As for chambering I have always wanted a 416 Rigby but may go with the 375 Remington Ultra Mag.
Once the action, barrel and chamber work are completed I will have it KG (Kal-Gard) coated or coated with a similar weatherproof finish. I will also have the Timney trigger adjusted to a 3lb trigger pull. I will then have it send to McMillan Fiberglass Stocks for a complete stock installation job, in my favorite molded-in camouflage pattern. LOP will be 13.75", stock will be padded with a Decelerator recoil pad. This is my plan for the rifle so far, strictly utilitarian for hunting in Alaska.
Nukalpiaq