The Duckworth 175 Sport 2010 is a deep-V design and the Duckworth 30 2010 is a modified-V design, so you're likely deciding between two noticeably different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
Size is the most obvious dividing line here. The Duckworth 30 2010 measures 30,0 feet overall (2010), giving it roughly 12,5 additional feet of deck space compared to the Duckworth 175 Sport 2010 at 17,5 feet (2010). Weight tells a clearer story for trailering families: the Duckworth 30 2010 tips the scales at 5 400 lbs - 3 945 lbs less than the Duckworth 175 Sport 2010 at 1 455 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 power gap is worth calling out. Rated to 500 hp, the Duckworth 30 2010 has a 385-hp advantage over the Duckworth 175 Sport 2010's 115-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Duckworth 30 2010 carries 130 gallons versus 42 gallons in the Duckworth 175 Sport 2010. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
For family outings this is probably the sharpest distinction between the two. The Duckworth 30 2010 is rated for 9 passengers, while the Duckworth 175 Sport 2010 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Duckworth 30 2010 could be the deciding factor.
Bottom line: Choose the Duckworth 30 2010 if your priority is putting more people on the water - it handles 9 passengers and at 30,0 ft it has the deck room to back that rating up comfortably. The Duckworth 175 Sport 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.