When two boats share the same hull type — in this case both the Bennington 165SLi 2009 and the Bennington 2577RFSIO 2009 are pontoon 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 Bennington 2577RFSIO 2009 measures 25,0 feet overall (2009), giving it roughly 9,0 additional feet of deck space compared to the Bennington 165SLi 2009 at 16,0 feet (2009). Weight tells a clearer story for trailering families: the Bennington 165SLi 2009 tips the scales at 1 491 lbs — 1 132 lbs more than the Bennington 2577RFSIO 2009 at 359 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 Bennington 165SLi 2009 has a 47-hp advantage over the Bennington 2577RFSIO 2009's 3-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 165SLi 2009 is rated for 6 passengers, while the Bennington 2577RFSIO 2009 caps at 3. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Bennington 165SLi 2009 could be the deciding factor.
Both are 2-tube and 3-tube pontoon designs respectively. Tube diameter and gauge affect stability and load capacity — more so than most buyers realize when comparing on paper.
Bottom line: Choose the Bennington 165SLi 2009 if your priority is putting more people on the water — it handles 6 passengers and at 16,0 ft it has the deck room to back that rating up comfortably. The Bennington 2577RFSIO 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 3 that costs less to run day-to-day.