I have a 18 foot Lund Alaskan with a 60 hp Mercury. I have a 9.9 kicker on it for back up but never use it as the 60 hp worked just fine. I ran it for 17 years and over 3000 hours! I actually just repowered with a 90 hp Yamaha and plan on trolling with it as well. Perhaps if you plan on going 1-1.2 mph you will need a trolling sock but I can troll 1.5- 2.8 all day long.