When two boats share the same hull type — in this case both the Supra Sunsport 20V 2010 and the Supra Sunsport 21V 2010 are modified vee designs with fiberglass 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?
On paper these two are close siblings in the size department — Supra Sunsport 20V 2010 at 20,7 ft versus Supra Sunsport 21V 2010 at 21,3 ft. At 31 lbs and 38 lbs respectively, both sit in a similar weight class — either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
Both boats share a closely matched power ceiling — 325 hp for the Supra Sunsport 20V 2010 and 325 hp for the Supra Sunsport 21V 2010. 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. Fuel capacity breaks the other way: the Supra Sunsport 21V 2010 carries 52 gallons versus 4 gallons in the Supra Sunsport 20V 2010. 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 Supra Sunsport 21V 2010 is rated for 14 passengers, while the Supra Sunsport 20V 2010 caps at 1. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Supra Sunsport 21V 2010 could be the deciding factor.
Bottom line: Choose the Supra Sunsport 21V 2010 if your priority is putting more people on the water — it handles 14 passengers and at 21,3 ft it has the deck room to back that rating up comfortably. The Supra Sunsport 20V 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 1 that costs less to run day-to-day.