Both the Dorado 30 LX Diesel I/O 2011 and the Dorado 42 Express 2011 are deep-V designs, both built in fibreglass, so 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 Dorado 42 Express 2011 measures 42,8 feet overall (2011), giving it roughly 12,8 additional feet of deck space compared to the Dorado 30 LX Diesel I/O 2011 at 30,0 feet (2011). Weight tells a clearer story for trailering families: the Dorado 42 Express 2011 tips the scales at 17 500 lbs - 12 000 lbs less than the Dorado 30 LX Diesel I/O 2011 at 5 500 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 Dorado 42 Express 2011 tops out at 450 hp. Engine specs for the Dorado 30 LX Diesel I/O 2011 aren't listed - confirm with a dealer before selecting an outboard.Fuel capacity breaks the other way: the Dorado 42 Express 2011 carries 400 gallons versus 100 gallons in the Dorado 30 LX Diesel I/O 2011. 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 Dorado 42 Express 2011 is rated for 13 passengers, while the Dorado 30 LX Diesel I/O 2011 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Dorado 42 Express 2011 could be the deciding factor.
Bottom line: Choose the Dorado 42 Express 2011 if your priority is putting more people on the water - it handles 13 passengers and at 42,8 ft it has the deck room to back that rating up comfortably. The Dorado 30 LX Diesel I/O 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 9 that costs less to run day-to-day.