Big engines… and I believe naturals have higher compression ratios. I would use starting batteries
My boat was 32v till I repowered and converted to 24. I used 8v golf cart batteries and used to get about 4 to 5 years life which is pretty good...
I use Aquamap the most, especially in the Bahamas as it uses explorer charts. The anchor alarm works great, very reliable with a late model...
Plans change all the times, they can’t make up their minds. Some users have reported buying the $2500 dish at resellers like Best Buy or RV...