When two boats share the same hull type — in this case both the Zodiac Medline III 2010 and the Zodiac Medline IV 2010 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 Zodiac Medline IV 2010 measures 27,9 feet overall (2010), giving it roughly 3,9 additional feet of deck space compared to the Zodiac Medline III 2010 at 24,0 feet (2010). Weight tells a clearer story for trailering families: the Zodiac Medline IV 2010 tips the scales at 3 527 lbs — 440 lbs less than the Zodiac Medline III 2010 at 3 087 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 350 hp, the Zodiac Medline IV 2010 has a 100-hp advantage over the Zodiac Medline III 2010's 250-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 Medline IV 2010 carries 106 gallons versus 47 gallons in the Zodiac Medline III 2010. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

Both boats are rated for 8 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.