Both the Avalon 20 ft. Paradise 2011 and the Avalon Tropic - 20 Foot 2008 are pontoon designs, both built in aluminium, 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?
On paper these two are close siblings in the size department - Avalon 20 ft. Paradise 2011 at 20,0 ft versus Avalon Tropic - 20 Foot 2008 at 20,0 ft. At 1 800 lbs and 1 870 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 115 hp, the Avalon 20 ft. Paradise 2011 has a 25-hp advantage over the Avalon Tropic - 20 Foot 2008's 90-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Avalon 20 ft. Paradise 2011 carries 36 gallons versus 24 gallons in the Avalon Tropic - 20 Foot 2008. 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 Avalon 20 ft. Paradise 2011 is rated for 10 passengers, while the Avalon Tropic - 20 Foot 2008 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Avalon 20 ft. Paradise 2011 could be the deciding factor.
Bottom line: Choose the Avalon 20 ft. Paradise 2011 if your priority is putting more people on the water - it handles 10 passengers and at 20,0 ft it has the deck room to back that rating up comfortably. The Avalon Tropic - 20 Foot 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 9 that costs less to run day-to-day.