The MG42 had no equal in the allied inventory, and the same could be said of the .50 cal for the axis side.
The MG42 works well as an anti-infantry weapon, although it can take down light vehicles if they stray too close.
The .50 cal doesn't have the ROF of the MG42, but it will mince most German HTs and A/Cs out to 500 meters. I suspect it would also chew its way through most of the buildings featured in CM.