No need for a levelling screw set up...
Some folks like the plate flat,,, I like mine on a up wards slop,,, that way I can push or pull the rifle into different spots to aline my optic target dot into the V ring with out adjusting the bag or rest...
The less fiddle F@rting around I do,,, the better off I am at remaining behind the rifle for the full shoot,,, once the land cannon is planted,,, my job is to remain in the drivers seat till the ride is complete...
The only thing that moves in my set is the loading and unloading hand,,, other than that it's eye behind the glass,,, or head down on the mat...
Life dosen't get any simpler then that...
Cheers