When two boats share the same hull type — in this case both the Zodiac 12 Man 2009 and the Zodiac ProJet 420 TC4 2008 are inflatable rigid designs with inflatable 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?
Both boats share a closely matched power ceiling — 90 hp for the Zodiac 12 Man 2009 and 98 hp for the Zodiac ProJet 420 TC4 2008. 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.
For family outings this is probably the sharpest distinction between the two. The Zodiac 12 Man 2009 is rated for 12 passengers, while the Zodiac ProJet 420 TC4 2008 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Zodiac 12 Man 2009 could be the deciding factor.
The Zodiac ProJet 420 TC4 2008 has a documented top speed of 40 mph. Speed data wasn't available for the other model.
Bottom line: Choose the Zodiac 12 Man 2009 if your priority is putting more people on the water — it handles 12 passengers and at 17,2 ft it has the deck room to back that rating up comfortably. The Zodiac ProJet 420 TC4 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.