Matching a inflatable rigid Zodiac Bayrunner Pro Series 2011 against a inflatable non rigid Zodiac Mark I ST 2009 means you're likely deciding between two genuinely different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
The Zodiac Mark I ST 2009 tops out at 25 hp. Engine specs for the Zodiac Bayrunner Pro Series 2011 aren't listed — confirm with a dealer before selecting an outboard.
For family outings this is probably the sharpest distinction between the two. The Zodiac Mark I ST 2009 is rated for 5 passengers, while the Zodiac Bayrunner Pro Series 2011 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Zodiac Mark I ST 2009 could be the deciding factor.
Bottom line: Choose the Zodiac Mark I ST 2009 if your priority is putting more people on the water — it handles 5 passengers and at 11,5 ft it has the deck room to back that rating up comfortably. The Zodiac Bayrunner Pro Series 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.