The Nautique Byerly 210 2009 is a modified-V design and the Nautique G23 2012 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.
On paper these two are close siblings in the size department - Nautique Byerly 210 2009 at 21,0 ft versus Nautique G23 2012 at 23,0 ft. Weight tells a clearer story for trailering families: the Nautique G23 2012 tips the scales at 5 400 lbs - 1 600 lbs less than the Nautique Byerly 210 2009 at 3 800 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 409 hp, the Nautique Byerly 210 2009 has a 66-hp advantage over the Nautique G23 2012's 343-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Nautique G23 2012 carries 65 gallons versus 40 gallons in the Nautique Byerly 210 2009. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
For family outings this is probably the sharpest distinction between the two. The Nautique G23 2012 is rated for 16 passengers, while the Nautique Byerly 210 2009 caps at 12. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Nautique G23 2012 could be the deciding factor.
Bottom line: Choose the Nautique G23 2012 if your priority is putting more people on the water - it handles 16 passengers and at 23,0 ft it has the deck room to back that rating up comfortably. The Nautique Byerly 210 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 12 that costs less to run day-to-day.