I am looking to purchase a new trolling motor. The choices I have narrowed down to are a bow mount Motor Guide pro series 46lb with cable operated pedal ,a MinnkotaEdge series 40lb. with cable or a Minnkota V2 power drive which is a 40 lb and has electric cord instead of a cable cord.The Minnkota cost about 60 dollars more.Which is better cable or electric.The other question I have is how long a shaft do I need.I have a 1991 Sylvan 16 ft deep V. The motor guide I'm looking at has a 50'' shaft. The Minnkota comes in a 48''shaft.