Matching a modified vee Riviera Yachts 51 Enclosed Flybridge SII 2010 against a deep vee Riviera Yachts 5800 Sport Yacht 2012 means you're likely deciding between two genuinely 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 — Riviera Yachts 51 Enclosed Flybridge SII 2010 at 54,7 ft versus Riviera Yachts 5800 Sport Yacht 2012 at 57,6 ft. Weight tells a clearer story for trailering families: the Riviera Yachts 5800 Sport Yacht 2012 tips the scales at 46 959 lbs — 42 153 lbs less than the Riviera Yachts 51 Enclosed Flybridge SII 2010 at 4 806 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 825 hp, the Riviera Yachts 51 Enclosed Flybridge SII 2010 has a 390-hp advantage over the Riviera Yachts 5800 Sport Yacht 2012's 435-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Riviera Yachts 51 Enclosed Flybridge SII 2010 carries 977 gallons versus 7 gallons in the Riviera Yachts 5800 Sport Yacht 2012. 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 Riviera Yachts 5800 Sport Yacht 2012 is rated for 17 passengers, while the Riviera Yachts 51 Enclosed Flybridge SII 2010 caps at 16. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Riviera Yachts 5800 Sport Yacht 2012 could be the deciding factor.