When two boats share the same hull type — in this case both the Duckworth 18 Sport 2011 and the Duckworth 21 2010 are deep vee designs with aluminum construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?

On paper these two are close siblings in the size department — Duckworth 18 Sport 2011 at 20,3 ft versus Duckworth 21 2010 at 21,0 ft. Weight tells a clearer story for trailering families: the Duckworth 18 Sport 2011 tips the scales at 1 455 lbs — 1 427 lbs more than the Duckworth 21 2010 at 28 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.

The Duckworth 18 Sport 2011 carries a rated maximum of 115 hp. Engine data for the Duckworth 21 2010 wasn't available in our records — check the manufacturer's spec sheet before sizing a motor.Fuel capacity breaks the other way: the Duckworth 21 2010 carries 62 gallons versus 42 gallons in the Duckworth 18 Sport 2011. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

Both boats are rated for 6 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.