I have the Yamaha F150, does about 50mph and gets great fuel mileage in the 25-40mph range.
Motors are not motors, some crank out less than sticker others more. A few years ago I saw a dyno test of the Yamaha F150 at 163hp..
Suzuki has a 4stroke 175 4cyl thats looking sweet.
So many choices!
Blazer Bay 2170, Yamaha F150, Minkota autopilot, Garman 178c