The Nordic Boats 21 ft. CrossFire 2010 is a modified-V design and the Nordic Boats 43 Enforcer 2009 is a catamaran 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 Nordic Boats 43 Enforcer 2009 measures 43,0 feet overall (2009), giving it roughly 22,0 additional feet of deck space compared to the Nordic Boats 21 ft. CrossFire 2010 at 21,0 feet (2010). Weight tells a clearer story for trailering families: the Nordic Boats 43 Enforcer 2009 tips the scales at 10 600 lbs - 7 800 lbs less than the Nordic Boats 21 ft. CrossFire 2010 at 2 800 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.
For family outings this is probably the sharpest distinction between the two. The Nordic Boats 43 Enforcer 2009 is rated for 13 passengers, while the Nordic Boats 21 ft. CrossFire 2010 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Nordic Boats 43 Enforcer 2009 could be the deciding factor.
Bottom line: Choose the Nordic Boats 43 Enforcer 2009 if your priority is putting more people on the water - it handles 13 passengers and at 43,0 ft it has the deck room to back that rating up comfortably. The Nordic Boats 21 ft. CrossFire 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.