Hello, my brother has I believe a 18 hp Koehler surface drive on a 16 foot Carolina Skiff, it will go almost anywhere, has had issues with clutch several times. You have to get motor to certain rpm for it to engage. It’s like riding your lawn tractor across the lake with the motor noise. Doesn’t go anywhere fast but will get you almost anywhere you need to go. To combat the rpm issue with the clutch he installed a manual switch to engage at low rpm to just Idle around. At full power it’s a little tiring to hold throttle and the tiller handle due to vibration and motor torque. Still a fun boat for short trips and getting where others dream about.