Matching a inflatable non rigid Mercury 340 Sport 2008 against a inflatable rigid Mercury 400 Amanzi Hypalon 2012 means you're likely deciding between two genuinely different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
On paper these two are close siblings in the size department — Mercury 340 Sport 2008 at 11,0 ft versus Mercury 400 Amanzi Hypalon 2012 at 13,0 ft. Weight tells a clearer story for trailering families: the Mercury 400 Amanzi Hypalon 2012 tips the scales at 775 lbs — 652 lbs less than the Mercury 340 Sport 2008 at 123 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 50 hp, the Mercury 400 Amanzi Hypalon 2012 has a 35-hp advantage over the Mercury 340 Sport 2008's 15-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load.
Both boats are rated for 5 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.
At this size, power-to-weight ratio matters more than outright horsepower. The Mercury 340 Sport 2008 comes in at 8 lbs per hp versus 16 lbs per hp for the Mercury 400 Amanzi Hypalon 2012. The lower the ratio the more explosive the acceleration — meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.
Bottom line: Performance buyers should lean toward the Mercury 400 Amanzi Hypalon 2012 and its 50-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Mercury 340 Sport 2008 with its 15-hp rating is the more economical daily driver.