Jeff, actually the 338/408 is a whole different rifle, it is an 8500 action, Lawton 9 twist Idaho taper 30 in. In length. It has an A3-5 stock. I like this stock much better than the A-5 that is on the 8000 action.
ELR, I have never tested a 375 with barrels longer than 30 inches, I don't know if the price of eggs would be worth the wear and tear on the hens posterior. If I were to build another 375, it would be a Lawton 8500 action, A3-5 Stock, 30 inch barrel. I have Lawton brakes on on both the 375 and the 338.
I have a 375 9-6 gain twist Sendero taper Bartlien barrel 30 inches in length. I will probably send it off this week to have it chambered for the 8500 action. This will give me a switch barrel rig that I can shoot the 338/408 or switch to the 375/408 with the heavy CE bullets. I had the 9-6 barrel made for bullets 7 calibers in length, the supply of those has since dried up. I think the 425CE will work well in this barrel.