Matching a pontoon Marathon Grumman Heritage H2185CPR 2010 against a modified vee Marathon Seneca 16RS 2013 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.
Size is the most obvious dividing line here. The Marathon Grumman Heritage H2185CPR 2010 measures 21,0 feet overall (2010), giving it roughly 5,0 additional feet of deck space compared to the Marathon Seneca 16RS 2013 at 16,0 feet (2013). Weight tells a clearer story for trailering families: the Marathon Seneca 16RS 2013 tips the scales at 312 lbs — 123 lbs less than the Marathon Grumman Heritage H2185CPR 2010 at 189 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 100 hp, the Marathon Grumman Heritage H2185CPR 2010 has a 60-hp advantage over the Marathon Seneca 16RS 2013's 40-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load.
For family outings this is probably the sharpest distinction between the two. The Marathon Grumman Heritage H2185CPR 2010 is rated for 12 passengers, while the Marathon Seneca 16RS 2013 caps at 7. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Marathon Grumman Heritage H2185CPR 2010 could be the deciding factor.
Bottom line: Choose the Marathon Grumman Heritage H2185CPR 2010 if your priority is putting more people on the water — it handles 12 passengers and at 21,0 ft it has the deck room to back that rating up comfortably. The Marathon Seneca 16RS 2013 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 7 that costs less to run day-to-day.