I have Optima Yellow D34 tops on my 24v motorguide. They never seem to run down.
I believe these are dual purpose deep cycle but they were already in the boat when I bought it.
My starting batteries are blue top D31
Infidel and proud of it.
From Genesis: "And God promised men that good and obedient wives would be found in all corners of the earth."
Then He made the earth round...and He laughed and laughed and laughed!