When two boats share the same hull type — in this case both the Voyager Marine Series 5600 2010 and the Voyager Marine Series 8500 - 1685 Open 2009 are flat designs with aluminum 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 Voyager Marine Series 8500 - 1685 Open 2009 measures 16,0 feet overall (2009), giving it roughly 4,0 additional feet of deck space compared to the Voyager Marine Series 5600 2010 at 12,0 feet (2010). Weight tells a clearer story for trailering families: the Voyager Marine Series 5600 2010 tips the scales at 145 lbs — 102 lbs more than the Voyager Marine Series 8500 - 1685 Open 2009 at 43 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 40 hp, the Voyager Marine Series 8500 - 1685 Open 2009 has a 30-hp advantage over the Voyager Marine Series 5600 2010's 10-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 Voyager Marine Series 5600 2010 is rated for 3 passengers, while the Voyager Marine Series 8500 - 1685 Open 2009 caps at 2. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Voyager Marine Series 5600 2010 could be the deciding factor.

At this size, power-to-weight ratio matters more than outright horsepower. The Voyager Marine Series 8500 - 1685 Open 2009 comes in at 1 lbs per hp versus 15 lbs per hp for the Voyager Marine Series 5600 2010. 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.