When two boats share the same hull type — in this case both the Zodiac Medline 580 2013 and the Zodiac Pro Classic 500 2013 are deep vee designs with rigid inflatable 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 Medline 580 2013 measures 19,0 feet overall (2013), giving it roughly 3,6 additional feet of deck space compared to the Zodiac Pro Classic 500 2013 at 15,4 feet (2013). Weight tells a clearer story for trailering families: the Zodiac Medline 580 2013 tips the scales at 1 325 lbs — 818 lbs more than the Zodiac Pro Classic 500 2013 at 507 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 — 80 hp for the Zodiac Medline 580 2013 and 70 hp for the Zodiac Pro Classic 500 2013. 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.
For family outings this is probably the sharpest distinction between the two. The Zodiac Medline 580 2013 is rated for 12 passengers, while the Zodiac Pro Classic 500 2013 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Zodiac Medline 580 2013 could be the deciding factor.
At this size, power-to-weight ratio matters more than outright horsepower. The Zodiac Pro Classic 500 2013 comes in at 7 lbs per hp versus 17 lbs per hp for the Zodiac Medline 580 2013. 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.
The Zodiac Pro Classic 500 2013 has a documented top speed of 41 mph. Speed data wasn't available for the other model.
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. 10 in. (0.55 m) on the Zodiac Medline 580 2013 vs 1 ft. 8 in. (0.5 m) on the Zodiac Pro Classic 500 2013 — larger tubes generally mean more buoyancy and a drier, more stable ride.
Bottom line: Choose the Zodiac Medline 580 2013 if your priority is putting more people on the water — it handles 12 passengers and at 19,0 ft it has the deck room to back that rating up comfortably. The Zodiac Pro Classic 500 2013 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 9 that costs less to run day-to-day.