A million dingy threads out there I know, but for what it's worth:
I think the same rule of thumb with boats in general applies to dingies too -- it's always a compromise. When we took our East Coast trip a couple months ago I got a new dingy from Defender (a Zodiac Zoom Aero 260, 8' 6", inflatable floor, about $699 on sale at the time) and a 4hp Yamaha 2-stroke motor from an elderly guy in Clinton Connecticut through Craigslist. He was funny, had about 100 outboard motors in his garage and backyard. Runs great, sold it to me for $400. I agonized over the size choices in the Defender showroom for over an hour. The salesman was very patient and helpful. It was really helpful to see them all there in person, blown up. My final choice was smaller than I originally planned but I just self-imposed some rules that helped me make the choice. (1) we don't have a davit or a derrick, so it had to be under 100 lbs; (2) almost everything I read is that solid floors are great, but very cumbersome to set up and break down and store, so I decided on an inflatable floor. I really hate soft-bottomed dingies that feel like you're walking on a waterbed but I have to say that Zodiac's inflatable floor is very solid. It uses a higher pressure than the tubes and I think it strikes a perfect balance between flexibility and rigidity. I think the slight flexibility gives it an even better ride over chop than a solid floor. It's really the best dingy ride I've ever felt for its size and style, and we've chartered a lot of boats with dingies before we bought our big boat. (3) I wanted at least one hard seat so we didn't have to all sit on the tubes getting splashed, or on the floor, getting our butts wet. (4) finally, one last size consideration was that it had to fit on the bow (we tow ours for short hops, but store it on the bow for longer runs), and we had to be able to wrestle it onto the bow with just my wife and me, without killing ourselves. The Zodiac just fits between the flybridge rise and the bow pulpit at 8' 6". I stand it up on the dock so it's resting on the ends of the pontoons, then I lift from the dock and my wife lifts from the bow and we flip it over the rail. Not fun, but not too bad. I really wanted a dingy big enough for two couples (four people), but had to compromise away from that. Any bigger or heavier and it would be an ordeal to flip onto the bow. It rates for three people. We could squeeze four into that dingy, but it's not a pleasant ride.
So there's my two cents. We're very happy with it, it's a lot of fun, and we actually use it far more than we expected (although ironically we never used it on the actual trip from Mass to Albany since we marina-hopped the whole way). We put six miles on that dingy to a beach up the river a couple weeks ago just for fun. And the dog likes it. And now I'm adding clip-on nav lights and a running light just for kicks.
Zodiac Nautic - Boats - Zoom 260 Aero
so I got on Craigslist and found a used 8' fatty knees, bought it yesterday. What a beautiful dink
