I had a 4 hp ob on a boat about the size of the Monty 17 but lighter displacement and had several hair raising experiences with the rig in Florida trying to motor into Government Cut in Miami as well as the Hillsborough Inlet further up the coast. When the wind was on the nose and the waves were 3 feet or so, forward progress was about nil. That experience at Government Cut in Miami involved a draw bridge, rush hour traffic and my boat inching forward under the span. I could see the bridge operator glaring down at me with his hand on the button. I did clear the bridge. It was closing as my stern eased out from under its shadow. Then I wondered what I would do if my screaming ob decided to quit at that moment. Not good thoughts. Was under powered years later on Lake Travis outside of Austin, Tx. 25 knots on the nose funneled between high banks on each side. Better a little too much power than not quite enough. Tom B