When two boats share the same hull type — in this case both the Maritime 18-D 2008 and the Maritime 20 Defiant 2012 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 — Maritime 18-D 2008 at 18,0 ft versus Maritime 20 Defiant 2012 at 20,6 ft. Weight tells a clearer story for trailering families: the Maritime 20 Defiant 2012 tips the scales at 204 lbs — 188 lbs less than the Maritime 18-D 2008 at 16 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 Maritime 20 Defiant 2012 tops out at 150 hp. Engine specs for the Maritime 18-D 2008 aren't listed — confirm with a dealer before selecting an outboard.Both carry nearly identical fuel loads — 29 gal and 29 gal — so range won't be a tiebreaker here.
For family outings this is probably the sharpest distinction between the two. The Maritime 20 Defiant 2012 is rated for 8 passengers, while the Maritime 18-D 2008 caps at 7. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Maritime 20 Defiant 2012 could be the deciding factor.
Bottom line: Choose the Maritime 20 Defiant 2012 if your priority is putting more people on the water — it handles 8 passengers and at 20,6 ft it has the deck room to back that rating up comfortably. The Maritime 18-D 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 7 that costs less to run day-to-day.