Actually, the fewer the number of cylinders, the more battery may be required due to the fewer numbers of firings. It doesn't offset the additional friction of draggin around eight slugs, but doesn't allow the battery requirements to be as small as you think. The four bangers have to crank faster for a few more turns to be fired vs. a V-8.
Here in Frozen North, MB OE batteries are minimum 800CCA, most are 1000CCA, and are nothing short of enormous.
I'd go for OEM or Optima.
1998 C230 "Black Betty"