The Baha Cruisers 266 Renaissance 2009 is a modified-V design and the Baha Cruisers 340 Mach 1/BR 2009 is a deep-V 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.
Size is the most obvious dividing line here. The Baha Cruisers 340 Mach 1/BR 2009 measures 34,2 feet overall (2009), giving it roughly 7,7 additional feet of deck space compared to the Baha Cruisers 266 Renaissance 2009 at 26,5 feet (2009). Weight tells a clearer story for trailering families: the Baha Cruisers 340 Mach 1/BR 2009 tips the scales at 9 500 lbs - 4 200 lbs less than the Baha Cruisers 266 Renaissance 2009 at 5 300 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.
For family outings this is probably the sharpest distinction between the two. The Baha Cruisers 340 Mach 1/BR 2009 is rated for 10 passengers, while the Baha Cruisers 266 Renaissance 2009 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Baha Cruisers 340 Mach 1/BR 2009 could be the deciding factor.
Bottom line: Choose the Baha Cruisers 340 Mach 1/BR 2009 if your priority is putting more people on the water - it handles 10 passengers and at 34,2 ft it has the deck room to back that rating up comfortably. The Baha Cruisers 266 Renaissance 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.