When two boats share the same hull type — in this case both the Campion Allante 645i BR 2011 and the Campion Allante 705i SC 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?

Size is the most obvious dividing line here. The Campion Allante 705i SC 2010 measures 26,2 feet overall (2010), giving it roughly 3,1 additional feet of deck space compared to the Campion Allante 645i BR 2011 at 23,1 feet (2011). Weight tells a clearer story for trailering families: the Campion Allante 645i BR 2011 tips the scales at 4 037 lbs — 3 582 lbs more than the Campion Allante 705i SC 2010 at 455 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 — 320 hp for the Campion Allante 645i BR 2011 and 320 hp for the Campion Allante 705i SC 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 Campion Allante 705i SC 2010 carries 69 gallons versus 56 gallons in the Campion Allante 645i BR 2011. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

Both boats are rated for 9 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.