When you stop and do the figures as to how much
fuel/cost you use compared to how little time/distance you actually gain. Unless you need to get back to the marina so you can get to the office by Monday, the best use for the engine is as a piece of safety equipment....(keeping you off of a lee shore in a nasty blow).
My boat has alot of sea miles under the keel, and only 1500 hours on the engine in the last 20 years