The Sylvan Mirage 8520 C 2011 vs Sylvan Pro Sport 1700 2006 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.
Size is the most obvious dividing line here. The Sylvan Mirage 8520 C 2011 measures 20,3 feet overall (2011), giving it roughly 3,3 additional feet of deck space compared to the Sylvan Pro Sport 1700 2006 at 17,0 feet (2006). At 185 lbs and 122 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.
Both boats share a closely matched power ceiling — 115 hp for the Sylvan Mirage 8520 C 2011 and 135 hp for the Sylvan Pro Sport 1700 2006. 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. Fuel capacity breaks the other way: the Sylvan Pro Sport 1700 2006 carries 31 gallons versus 24 gallons in the Sylvan Mirage 8520 C 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 Sylvan Mirage 8520 C 2011 is rated for 12 passengers, while the Sylvan Pro Sport 1700 2006 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sylvan Mirage 8520 C 2011 could be the deciding factor.
Bottom line: Choose the Sylvan Mirage 8520 C 2011 if your priority is putting more people on the water — it handles 12 passengers and at 20,3 ft it has the deck room to back that rating up comfortably. The Sylvan Pro Sport 1700 2006 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.