Bigger is definately better, I'm in the process of putting a 101lb on my rig, got tired of barely making head weight in the current or not making head weight at all depending on where I was with my 55lb. My buddies are taking bets if I'll get that boat on plane with the 101. I already carry 1 cranking and 2 trolling motor bateries, just gonna wire the cranking in with the others so it will be no more batteries than what I was already carrying, plus I carry a jump box with me too so I'm not worried about killing the main battery but I don't see where it will ever come to that point.