Both the Bennington 18 SF 2013 and the Bennington 2050SF 2009 are pontoon 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 - Bennington 18 SF 2013 at 18,4 ft versus Bennington 2050SF 2009 at 20,0 ft. At 1 663 lbs and 1 745 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 50 hp, the Bennington 18 SF 2013 has a 27-hp advantage over the Bennington 2050SF 2009's 23-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 Bennington 2050SF 2009 is rated for 23 passengers, while the Bennington 18 SF 2013 caps at 7. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Bennington 2050SF 2009 could be the deciding factor.
One place where both boats are genuinely identical is tube construction: both run 2 aluminum tubes at 23" diameter. That shared spec means stability and buoyancy characteristics are closely matched - the ride difference you'll feel between them comes primarily from deck length, weight distribution, and motor choice.
Bottom line: Choose the Bennington 2050SF 2009 if your priority is putting more people on the water - it handles 23 passengers and at 20,0 ft it has the deck room to back that rating up comfortably. The Bennington 18 SF 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.