I’m using FFS, TRASOL, STRELOKpro and in the past CB1, CB1 and FFS are very close, two good engines, I don’t like CB1 interface but this is another story, the engine is good.
using same data DA 0 meters, same speed, G7 BC for TRASOL and Strelokpro .415 ( AB book CE MTH L 350 ) and 0.871 for FFS...