Get as BIG as you can afford. There is a BIG jump in price to a 50 lb'er. I have one on my 14' Northwood and that motor pushes it along at 3 MPH. If you are fishing BIG water like Samm and Washington a lot you may want to hold out for a gas motor. Even though electrics are ideal for trolling. Either way you won't go wrong with electric and gas. I have both.