campn4walleye - I understood you were referring to TC batteries and not the truck. I apologize for taking the thread off track.
My position is the same. It will probably start a war, but I think 6-volt batteries in a TC is based on old technology. I also prefer to use the 12-volt for replacement, and availability. I will go a step further in saying I feel very strongly that AGMs are the best choice for a TC if it is affordable. This is especially true if you store your TC for long periods of time, or lax in battery maintenance.
Wayne