The SouthWind 2010 L 2008 is a pontoon design and the SouthWind 229 FF 2009 is a tri-hull design, so you're likely deciding between two noticeably different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
On paper these two are close siblings in the size department - SouthWind 2010 L 2008 at 20,0 ft versus SouthWind 229 FF 2009 at 22,8 ft. Weight tells a clearer story for trailering families: the SouthWind 229 FF 2009 tips the scales at 3 500 lbs - 300 lbs less than the SouthWind 2010 L 2008 at 3 200 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 - 115 hp for the SouthWind 2010 L 2008 and 115 hp for the SouthWind 229 FF 2009. 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. Both carry nearly identical fuel loads - 35 gal and 35 gal - so range won't be a tiebreaker here.
For family outings this is probably the sharpest distinction between the two. The SouthWind 229 FF 2009 is rated for 11 passengers, while the SouthWind 2010 L 2008 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the SouthWind 229 FF 2009 could be the deciding factor.
Bottom line: Choose the SouthWind 229 FF 2009 if your priority is putting more people on the water - it handles 11 passengers and at 22,8 ft it has the deck room to back that rating up comfortably. The SouthWind 2010 L 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 9 that costs less to run day-to-day.