I'd take that you would be testing the cold start capabilities more than most. Some extra MCCA capacity over the normal engine requirements, would probably be a good thing.
Wow. I have 3 Everstarts that came with my boat. 2 are 5 yrs old and one is 6 yrs old and while I know they're due for replacement, they're still working quite well. Must be good batteries....???
I just recently upgraded my batteries to Vmax Charge Tanks and i am very happy. A bit more expenseve, but a very good AGM deep cylce battery. I am currently using the MR-127. Good luck.