When two boats share the same hull type — in this case both the Excel Boats 1645SWF4 2011 and the Excel Boats 1851SWV4 2011 are modified vee 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?

On paper these two are close siblings in the size department — Excel Boats 1645SWF4 2011 at 16,0 ft versus Excel Boats 1851SWV4 2011 at 18,0 ft. Weight tells a clearer story for trailering families: the Excel Boats 1851SWV4 2011 tips the scales at 714 lbs — 667 lbs less than the Excel Boats 1645SWF4 2011 at 47 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.

Both boats share a closely matched power ceiling — 7 hp for the Excel Boats 1645SWF4 2011 and 7 hp for the Excel Boats 1851SWV4 2011. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup.

For family outings this is probably the sharpest distinction between the two. The Excel Boats 1851SWV4 2011 is rated for 4 passengers, while the Excel Boats 1645SWF4 2011 caps at 3. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Excel Boats 1851SWV4 2011 could be the deciding factor.

At this size, power-to-weight ratio matters more than outright horsepower. The Excel Boats 1645SWF4 2011 comes in at 7 lbs per hp versus 102 lbs per hp for the Excel Boats 1851SWV4 2011. 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.