Both the Larson 218 LXi 2010 and the Larson Senza 186 O/B 2007 are modified-V designs, both built in fibreglass, 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 Larson 218 LXi 2010 measures 21,5 feet overall (2010), giving it roughly 3,5 additional feet of deck space compared to the Larson Senza 186 O/B 2007 at 18,0 feet (2007). Weight tells a clearer story for trailering families: the Larson 218 LXi 2010 tips the scales at 3 735 lbs - 1 950 lbs more than the Larson Senza 186 O/B 2007 at 1 785 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 Larson Senza 186 O/B 2007 tops out at 175 hp. Engine specs for the Larson 218 LXi 2010 aren't listed - confirm with a dealer before selecting an outboard.Fuel capacity breaks the other way: the Larson 218 LXi 2010 carries 34 gallons versus 29 gallons in the Larson Senza 186 O/B 2007. 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 Larson 218 LXi 2010 is rated for 9 passengers, while the Larson Senza 186 O/B 2007 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Larson 218 LXi 2010 could be the deciding factor.
Bottom line: Choose the Larson 218 LXi 2010 if your priority is putting more people on the water - it handles 9 passengers and at 21,5 ft it has the deck room to back that rating up comfortably. The Larson Senza 186 O/B 2007 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.