In a very general sense, the only major differences between the TheMightyHobie18 and the H16 are that the 18 has dagger boards, so you have to remember to put them down and then pull them up when you come in (it shouldn't take you long to figure that one out). And the 18 is a much more stable platform. It has a lot more volume in the bows so much lower tendency to want to pitchpole. Otherwise, they are quite similar.

As mentioned above, a lot is going to depend on the condition of the boat itself. If it's an old clunker, half full of water, not rigged properly, etc, you probably won't be able to do much more than cruise around at low speed.

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