Matching a flat Weld-Craft CLT 70 (20 ft.) 2009 against a modified vee Weld-Craft Duck 2013 means you're likely deciding between two genuinely different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
Both boats share a closely matched power ceiling — 40 hp for the Weld-Craft CLT 70 (20 ft.) 2009 and 25 hp for the Weld-Craft Duck 2013. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup.
For family outings this is probably the sharpest distinction between the two. The Weld-Craft CLT 70 (20 ft.) 2009 is rated for 6 passengers, while the Weld-Craft Duck 2013 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Weld-Craft CLT 70 (20 ft.) 2009 could be the deciding factor.
Bottom line: Choose the Weld-Craft CLT 70 (20 ft.) 2009 if your priority is putting more people on the water — it handles 6 passengers and at 2,0 ft it has the deck room to back that rating up comfortably. The Weld-Craft Duck 2013 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.