My first powerful rifle was a .350 magnum, and I came away from the experience with some opinions that I still hold. The first is that the bedding of a powerful rifle must be done properly if the stock is going to stand up, my .350's stock, it was an early M-700, split well up into the checkering of the forend to the front and clear through the pistol grip behind the tang.
I learned that sometimes gunsmiths have a long turnaround time, and the one I chose went bankrupt before I got the rifle back. Those Manitoba Gunnutz whose memory extends back to the early '70s might recall who that was. I got the rifle back after what seemed to be an eternity and until it was in my hands I wasn't sure it ever would be or that I would be compensated.
I learned that despite the opinion pieces that were written at the time, the .350 was capable of very good accuracy.
I learned that cartridges larger than .30 caliber did better with longer rather than short fat cases, and long and fat is better yet. Thus a .35 Whelen can be loaded with heavier bullets without having to deal with compressed loads that plague the .350 magnum, and a .35 Ultra would make a very cool, easy to load wildcat.