The Eliminator 21 ft. Low Profile Daytona 2009 is a catamaran design and the Eliminator 300 Eagle XP 2012 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 Eliminator 300 Eagle XP 2012 measures 29,0 feet overall (2012), giving it roughly 8,0 additional feet of deck space compared to the Eliminator 21 ft. Low Profile Daytona 2009 at 21,0 feet (2009). Weight tells a clearer story for trailering families: the Eliminator 300 Eagle XP 2012 tips the scales at 5 800 lbs - 3 600 lbs less than the Eliminator 21 ft. Low Profile Daytona 2009 at 2 200 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 Eliminator 300 Eagle XP 2012 is rated for 6 passengers, while the Eliminator 21 ft. Low Profile Daytona 2009 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Eliminator 300 Eagle XP 2012 could be the deciding factor.
Bottom line: Choose the Eliminator 300 Eagle XP 2012 if your priority is putting more people on the water - it handles 6 passengers and at 29,0 ft it has the deck room to back that rating up comfortably. The Eliminator 21 ft. Low Profile Daytona 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.