What xausa said (sort of...)

Regarding the "butter-knife" bolt-handle, it is my belief that they are inappropriate when the bolt-handle is attached behind the rear bridge, as on the Mausers pictured.

Having owned and hunted with MS rifles for several decades, frequently reloading at the shoulder in the thick of things, I have come to understand that the flat Mannlicher-style bolt-handle works by placing the thumb on the top of the "root" and lifting with the fingers. This is a piece of cake (and very fast!) if the handle is forward of a split-bridge, but not ergonomic at all if the rear mount-base, bolt-shroud flange, and cocking-piece safety are all conspiring to get in the way.

And don't get me started on the swept-back butter-knife bolt-handle demanded by the American market in the 1950s: utterly defeats the purpose, and of course, ultimately caused the demise of this marvelous genre of classic hunting rifles.

Just my humble opinion BTW, worth precisely what you paid for it.

Happy to consider thoughts and experiences from Mauser Type M users...?

As for the ugly(?) panel-beaten example discussed above, not my cup of tea at all I'm afraid.