Both the Starcraft Marine 12 SL 2012 and the Starcraft Marine 2100 2010 are modified-V designs, both built in aluminium, so 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?
Size is the most obvious dividing line here. The Starcraft Marine 2100 2010 measures 20,8 feet overall (2010), giving it roughly 9,1 additional feet of deck space compared to the Starcraft Marine 12 SL 2012 at 11,8 feet (2012). Weight tells a clearer story for trailering families: the Starcraft Marine 2100 2010 tips the scales at 1 715 lbs - 1 603 lbs less than the Starcraft Marine 12 SL 2012 at 112 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.
The power gap is worth calling out. Rated to 250 hp, the Starcraft Marine 2100 2010 has a 240-hp advantage over the Starcraft Marine 12 SL 2012's 10-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load.
For family outings this is probably the sharpest distinction between the two. The Starcraft Marine 2100 2010 is rated for 10 passengers, while the Starcraft Marine 12 SL 2012 caps at 3. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Starcraft Marine 2100 2010 could be the deciding factor.
Bottom line: Choose the Starcraft Marine 2100 2010 if your priority is putting more people on the water - it handles 10 passengers and at 20,8 ft it has the deck room to back that rating up comfortably. The Starcraft Marine 12 SL 2012 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 3 that costs less to run day-to-day.