So, my wife picked up my order of RL-17 from Ronster on Monday when she was in town and I promptly loaded up some test rounds. I used Norma brass, 210M primers, and 150 grain Remington Core-lokt bullets. I reached the max published charge, 58.0 grains, without any signs of pressure.
I didn't chrono the loads, but merely checked for accuracy. My gun, a Kimber Montana with the barrel shortened to 21", normally prefers mid to faster powders with these bullets. I've had excellent luck with RL-15 and Varget in this gun, normally getting 1 1/4" five shot groups with little wait time between shots. The RL-17 was on par with my accuracy results from RL-19, getting about 2" groups. Three five shot groups confirmed, at least in my mind, that I would be sticking with Varget in this gun with these bullets.
When I get time I'm going to try RL-17 with some 165 and 180 grain bullets in this gun and my wife's .300 WSM.