Both the Mariah G21 2012 and the Mariah R19 2011 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?
On paper these two are close siblings in the size department - Mariah G21 2012 at 21,4 ft versus Mariah R19 2011 at 19,2 ft. At 3 600 lbs and 3 650 lbs respectively, both sit in a similar weight class - either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
The power gap is worth calling out. Rated to 300 hp, the Mariah G21 2012 has a 75-hp advantage over the Mariah R19 2011's 225-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads - 35 gal and 38 gal - so range won't be a tiebreaker here.
Both boats are rated for 10 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 G21 2012 at 21,4 ft is the right call if deck space, comfort, and entertaining are top of your list. The Mariah R19 2011 at 19,2 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.