The Sundance B20 CX 2006 vs Sundance NX21 2010 comparison sits squarely in the category of decisions where specs alone won't tell the whole story: intended use, storage, and long-term ownership costs all factor in.
On paper these two are close siblings in the size department - Sundance B20 CX 2006 at 19,0 ft versus Sundance NX21 2010 at 21,1 ft. Weight tells a clearer story for trailering families: the Sundance NX21 2010 tips the scales at 1 850 lbs - 255 lbs less than the Sundance B20 CX 2006 at 1 595 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.
Both boats share a closely matched power ceiling - 130 hp for the Sundance B20 CX 2006 and 115 hp for the Sundance NX21 2010. 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. Fuel capacity breaks the other way: the Sundance NX21 2010 carries 45 gallons versus 33 gallons in the Sundance B20 CX 2006. 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 Sundance B20 CX 2006 is rated for 11 passengers, while the Sundance NX21 2010 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sundance B20 CX 2006 could be the deciding factor.
Bottom line: Choose the Sundance B20 CX 2006 if your priority is putting more people on the water - it handles 11 passengers and at 19,0 ft it has the deck room to back that rating up comfortably. The Sundance NX21 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.