When two boats share the same hull type — in this case both the Zodiac Pro Open 550 2012 and the Zodiac Yachtline Deluxe 420 DL 2012 are inflatable rigid 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 Zodiac Pro Open 550 2012 measures 18,1 feet overall (2012), giving it roughly 4,3 additional feet of deck space compared to the Zodiac Yachtline Deluxe 420 DL 2012 at 13,8 feet (2012). Weight tells a clearer story for trailering families: the Zodiac Pro Open 550 2012 tips the scales at 882 lbs — 280 lbs more than the Zodiac Yachtline Deluxe 420 DL 2012 at 602 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 120 hp, the Zodiac Pro Open 550 2012 has a 60-hp advantage over the Zodiac Yachtline Deluxe 420 DL 2012's 60-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Zodiac Pro Open 550 2012 carries 22 gallons versus 15 gallons in the Zodiac Yachtline Deluxe 420 DL 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 Zodiac Pro Open 550 2012 is rated for 11 passengers, while the Zodiac Yachtline Deluxe 420 DL 2012 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Zodiac Pro Open 550 2012 could be the deciding factor.
At this size, power-to-weight ratio matters more than outright horsepower. The Zodiac Pro Open 550 2012 comes in at 7 lbs per hp versus 10 lbs per hp for the Zodiac Yachtline Deluxe 420 DL 2012. The lower the ratio the more explosive the acceleration — meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.
Top speed is rated at 45 mph for the Zodiac Pro Open 550 2012 and 37 mph for the Zodiac Yachtline Deluxe 420 DL 2012.
Both are inflatable designs, which means they pack down for compact storage, can be carried in a bag, and are dramatically lighter than equivalent rigid hulls. The trade-off is setup time and the need to monitor tube pressure regularly. Tube diameter differs: 1 ft. 11 in. (0.575 m) on the Zodiac Pro Open 550 2012 vs 1 ft. 6 in. (0.455 m) on the Zodiac Yachtline Deluxe 420 DL 2012 — larger tubes generally mean more buoyancy and a drier, more stable ride.
Bottom line: Choose the Zodiac Pro Open 550 2012 if your priority is putting more people on the water — it handles 11 passengers and at 18,1 ft it has the deck room to back that rating up comfortably. The Zodiac Yachtline Deluxe 420 DL 2012 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.