When two boats share the same hull type — in this case both the ProKat 2660 Walk Around 2008 and the ProKat 3660 Express 2007 are catamaran 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 ProKat 3660 Express 2007 measures 37,0 feet overall (2007), giving it roughly 10,0 additional feet of deck space compared to the ProKat 2660 Walk Around 2008 at 27,0 feet (2008). At 51 lbs and 148 lbs respectively, both sit in a similar weight class — either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
The power gap is worth calling out. Rated to 650 hp, the ProKat 3660 Express 2007 has a 150-hp advantage over the ProKat 2660 Walk Around 2008's 500-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the ProKat 2660 Walk Around 2008 carries 252 gallons versus 3 gallons in the ProKat 3660 Express 2007. 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 ProKat 3660 Express 2007 is rated for 11 passengers, while the ProKat 2660 Walk Around 2008 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the ProKat 3660 Express 2007 could be the deciding factor.
Bottom line: Choose the ProKat 3660 Express 2007 if your priority is putting more people on the water — it handles 11 passengers and at 37,0 ft it has the deck room to back that rating up comfortably. The ProKat 2660 Walk Around 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.