For myself a nearly straight comb seems best. But I always use a scope. On my CZ550 in .458 Win Mag that was loaded "long", and easily matched Lott loads, recoil was quite manageable from bench-rest style. My smith added some weight to the forearm which brought hunting weight (with scope, sling and ammo) to just over 11 lbs. That was in using 500s at 2250 to 2285 fps from 81 grs powder.
Your 450 will be more, of course, depending on load. But my #1 Ruger in .45-70 with a long throat (LT), was equal to a .458 Win Mag shooting a 500 at 2200 fps. It weighed a mere 8.3 lbs and recoil would be up there with your 450 at about 75 ft-lbs. It too had a near straight stock. That was replaced last year with a #1 Ruger in .458 Win, and I've been developing loads for it since at Lott levels, since it has no magazine and a very long leade. But recoil is less than my former #1 in .45-70 LT. That was the point due to five stents last year and cataract surgery a few weeks ago. I wanted the same ballistics with less recoil. This Ruger Tropical also has Mag-na-porting. At midway between 83 and 84, I'm also now using a Lead Sled at the range for testing purposes.
But the point is, from my experience, that rifle weight is more critical than the comb being slightly higher or lower. But I prefer straight, or nearly so. (Edit: the #1 Ruger in .458 is also 2 lbs heavier than my former #1 in .45-70 LT)
Bob
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