My polarkraft is 18' with a 60" bottom. I would not want less than the Terrova 80 that I have. On a calm day, I can pull for about 6 to 7 hours at 2mph with the group 29's. I usually use the big motor and steer with the trolling motor into the wind, trolling motor only with the wind, never run out of juice. With less thrust, the motor is going to have to work harder, therefore using more power.
I can promise you one thing, you will forget your i-pilot remote or the battery will be dead. When that happens, you are dead in the water with the Pd. With the Terrova you just pull the foot control out, plug it in and continue fishing. Well worth the extra money, to me anyway.
Carl's Guide Service
Sardis Lake
Enid Lake
Grenada Lake
901-734-7536