I owned that #1 in .460 for most of it's life and used it a fair bit. When I had it there was no Magna-porting, but it did have the removable muzzle brake. The Decelerator pad helped more than everything else, and with the new R3 pads and so on out now, I would likely put one of those on it.
The .460 round is actually quite versatile, it doesn't have to be loaded to the top end all the time. It can imitate the ballistics of any other .45 rifle round. My favorite load in it for hunting was a 400 grain Barnes X spitzer at 2500 fps. it just toppled big animals and was really easy to shoot.
That rifle is capable of some very good accuracy too and you will never be limited by powder capacity, it will do all that you will ever want and more. The rifle has potential beyond what most shooters are going to want to hold onto.
It worked well with cast bullets and filler too for reduced loads. Loading it like a .45/90, it will give accuracy for bench shooting with cast bullets. If you want to load a 300 grainer or 350 up and make it shoot flat, it will do that too. It will also take the middle weight bullets in 400-405 and up and shoot them at medium velocities without any trouble.
Top end loads will burn a lot of powder, but you know that getting into it.
Weatherby adds an extra recoil lug to their Mark Vs in .460. I don't know anything about the Sako rifles, so I can't say what they would need, but you can bet there is a good reason Weatherby adds that second lug to their .460s, maybe someone with experience with Sakos could tell us if it's required here.
The .460 when loaded up to it's potential kicks fast and heavily, it's something that takes a lot of shooting to get used too. I find it similar in feel to a heavy load from a .416 Rigby only scaled up another 1/4. That #1 is worse than a Mark V for recoil too, as that Tropical weighed just 9 lbs. even before you added the weight to it. That rifle started life as a .458 Win, then was a .450 AI and finally a .460Wby. The sights were done by an old well known smith in Whitehorse and the barrel was done by Ron Propp or Ralf Martini, I forget which. The finish was just added before it left here. That rifle was always very accurate and spawned lots of ideas and #1 projects after it including some other .45s and .50s. It's a great rifle, but you have to work it up. Full house rounds to start off with and you will never want to shoot it. Shot-buffer works great for filler for reduced loads in that case too.