I don't have the CZ 550 Safari Magnum. However, I have what I believe is a nearly identical rifle in .458 Winchester Magnum...the BRNO 602ZKK. Mine has the European "hogsback" stock.
When I first fired the rifle, I fired it with a friend who gave me left over ammunition he had from a rifle he once owned. He had owned a Ruger M77 in .458 Winchester Magnum and said it kicked like a mule.
We were both very surprised at the light recoil of my BRNO using the same ammunition that produced brutal recoil in the Ruger. The only hypothesis I could come up with is that the European style stock dampens felt recoil. It certainly wasn't due to the hard rubber recoil pad.
Later, I wanted a comparable .308. The only offering CZ had in .308 with the European style buttstock was the CZ550FS. I bought it and it also is noticeably lighter in felt recoil than other bolt action .308's I own.
My considered opinion is that the European style stocks handle recoil better than the American style stocks do. However, this is based on experience with only two rifles and two calibers.
I can think of no other explanation for the difference in felt recoil in these two rifles when compared with American stocked rifles of comparable weight shooting ammunition from the same box.