When two boats share the same hull type — in this case both the Sundance B20CC 2009 and the Sundance NX21 2010 are modified vee designs with fiberglass 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 — Sundance B20CC 2009 at 19,8 ft versus Sundance NX21 2010 at 21,1 ft. At 181 lbs and 185 lbs respectively, both sit in a similar weight class — either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
The power gap is worth calling out. Rated to 115 hp, the Sundance NX21 2010 has a 25-hp advantage over the Sundance B20CC 2009's 90-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Sundance NX21 2010 carries 45 gallons versus 33 gallons in the Sundance B20CC 2009. 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 NX21 2010 is rated for 8 passengers, while the Sundance B20CC 2009 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sundance NX21 2010 could be the deciding factor.
Bottom line: Choose the Sundance NX21 2010 if your priority is putting more people on the water — it handles 8 passengers and at 21,1 ft it has the deck room to back that rating up comfortably. The Sundance B20CC 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.