On 2008-02-21 23:55:55 -0500, Wayne.B said:

We've had good experiences with both a 12 ft Avon roll up with
aluminum floor and inflatable keel, and also an 11 ft Caribe RIB. We
have used a 15 hp Merc in the past but presently have a 20 hp Honda.
They will plane off at 15+ kts with 3 people on board but struggle with
4. They both require a hoist and a fair amount of deck space for
storage.

On the other hand, our 12.5' PortaBote delivers 10+ knots with 300+
pounds of people onboard with 4 HP, and planed at about the same speed
with 5 adults powered by a 7.5 Honda high-thrust sailboat kicker.

I'd be afraid to throw 15 hp into our PortaBote with any number aboard,
as the likely speeds would be truly beyond my comfort level. 20 hp? No
chance I'd open the throttle to full.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI trips & tips: http://homepage.mac.com/jerelull/BVI/