When two boats share the same hull type — in this case both the Mariah FS20 2010 and the Mariah R21 2011 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?
Size is the most obvious dividing line here. The Mariah R21 2011 measures 21,4 feet overall (2011), giving it roughly 19,4 additional feet of deck space compared to the Mariah FS20 2010 at 2,0 feet (2010). Weight tells a clearer story for trailering families: the Mariah FS20 2010 tips the scales at 355 lbs — 321 lbs more than the Mariah R21 2011 at 34 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 300 hp, the Mariah R21 2011 has a 40-hp advantage over the Mariah FS20 2010's 260-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads — 38 gal and 36 gal — so range won't be a tiebreaker here.
Both boats are rated for 1 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.
Bottom line: The Mariah R21 2011 at 21,4 ft is the right call if deck space, comfort, and entertaining are top of your list. The Mariah FS20 2010 at 2,0 ft wins on trailering ease, likely lower purchase price, and simpler docking — a solid choice for a buyer who wants more boat for less money.