Both the Bennington 17 SLi 2011 and the Bennington 2575RL I/O 2008 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?
Size is the most obvious dividing line here. The Bennington 2575RL I/O 2008 measures 25,0 feet overall (2008), giving it roughly 7,6 additional feet of deck space compared to the Bennington 17 SLi 2011 at 17,4 feet (2011). Weight tells a clearer story for trailering families: the Bennington 2575RL I/O 2008 tips the scales at 3 150 lbs - 1 659 lbs less than the Bennington 17 SLi 2011 at 1 491 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 Bennington 2575RL I/O 2008 tops out at 425 hp. Engine specs for the Bennington 17 SLi 2011 aren't listed - confirm with a dealer before selecting an outboard.
For family outings this is probably the sharpest distinction between the two. The Bennington 2575RL I/O 2008 is rated for 14 passengers, while the Bennington 17 SLi 2011 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Bennington 2575RL I/O 2008 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 2575RL I/O 2008 if your priority is putting more people on the water - it handles 14 passengers and at 25,0 ft it has the deck room to back that rating up comfortably. The Bennington 17 SLi 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.