This article is from the Sea Kayaking FAQ, by Todd Leigh with numerous contributions by others.
The best way to choose a boat, and the only way to determine its
paddling characteristics, is to try it, and you should take
opportunities to try as many boats as you can to decide what you
like. Many shops have demo days, and symposia are good opportunities
to try boats. Try to find an opportunity to paddle in the conditions
you are planning on using the boat in. Also, consider how the boat
handles when it is loaded as well as unloaded. Things to think about
when you are trying the boat are:
Does it feel comfortable just sitting in it?
Lean the boat onto it's side. Does it stop leaning or keep going and
tip over? Is there a point where the resistance to leaning increases?
Paddle the boat into the wind, across the wind, with the wind behind
you. How easy is it to keep on course? Does it turn into the wind
(weathercocking) or out of the wind excessively? How fast is it?
How easy is the boat to turn?
These things test some of the fundamental characteristics of boat
handling:
Speed - a function of length, width, and hull shape.
Tracking - ability of the boat to go straight.
Maneuverability - ability of the boat to turn easily.
Initial or primary stability - effort it takes to lean the boat off of an
upright position.
Final or secondary stability - effort it takes to tip the boat over.
Typical trade-offs:
Tracking vs. Maneuverability
Initial vs. Final Stability
Speed vs. Stability
 
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