Seriously?
The 5 men Infantry sections and Riflemen both can get dual LMGs/BARs.While the 4 men Grenedier can get only one LMG upgrade. Not to mention 1 gren model cost 30MP which is the most expensive. Also the receive accuracy is worse than infantry sections and Riflemen.
So how the Grens handle Riflemen or IS? We must not be playing the same game. Grenediers always suffer from heavier casualties in late game compared to other basic infantry. And Grens always lose to late game IS or Riflemen.
Double bars is a double edge sword here, losing this squad will push you back. Grens have amazing grenades and they do fairly well at long ranges with MG-42s. If you are comparing blobs, I suggest using combined arms such as MG, Gren and Mortar combo.