When two boats share the same hull type — in this case both the Riviera Yachts 45 Open Flybridge Shaft Drive 2012 and the Riviera Yachts 78 Motor Yacht 2011 are deep 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 Riviera Yachts 78 Motor Yacht 2011 measures 78,0 feet overall (2011), giving it roughly 26,8 additional feet of deck space compared to the Riviera Yachts 45 Open Flybridge Shaft Drive 2012 at 51,3 feet (2012). Weight tells a clearer story for trailering families: the Riviera Yachts 78 Motor Yacht 2011 tips the scales at 13 426 lbs — 13 032 lbs less than the Riviera Yachts 45 Open Flybridge Shaft Drive 2012 at 394 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 1 015 hp, the Riviera Yachts 78 Motor Yacht 2011 has a 345-hp advantage over the Riviera Yachts 45 Open Flybridge Shaft Drive 2012's 670-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 78 Motor Yacht 2011 carries 2 117 gallons versus 608 gallons in the Riviera Yachts 45 Open Flybridge Shaft Drive 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 78 Motor Yacht 2011 is rated for 23 passengers, while the Riviera Yachts 45 Open Flybridge Shaft Drive 2012 caps at 14. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Riviera Yachts 78 Motor Yacht 2011 could be the deciding factor.