The new beta will actually buff the build a bit. Sprint will be available without BP1 but will cost 20 muni. That will help a lot with closing the distance in early engagements. With mechanized if you do well fuel wise you can get Stug E after BP2. Against soviet T1 it can be extremely punishing as long as you support it against PTRS Penal and Guards. USF LT doesn't have a great counter so it will bleed them fairly well.
Yeah, that got me interested in Ass Grens in the first place. I only used it a few times before.
Would you suggest going for Assault Grenadiers against USF if the player has Mechanized/WC51?