Things I look for when shopping for a new suit. Let me know if I miss anything important:

• Fit. Try on different sizes, different suits (companies have several different types of suit with different names), and different wetsuit manufacturers.
   
• Neoprene type. 'Smoothie' neoprene tends to stretch better, look better, and is warmer esp. in windy conditions. It is also a little more susceptible to damage than the neoprene with fabric on the outside. Some suits now use a polypropylene lining on the inside which helps to repel the water and keep you a little warmer.
   
• Seams. These connect the panels of neoprene. Generally speaking, more panels in a suit design means better flexibility. It also means more places for water to get in. There are a few types of seams used:
   
  • Overlock. This is found on the least expensive suits. This type of stitch lasts forever, is not watertight, and can cause skin irritation or rash as it protrudes a lot.
     
  • Flatlock. A flat stitch that doesn't push into your skin like the overlock stitching. It is not as durable as the overlock stitch, but does not cause as much rash problems. This is also not a watertight stitch.
     
  • Blindstitch. Blindstitching is flat and does not penetrate through to the other side of the neoprene, so there are no stitch holes for cold water to follow. Double-blindstitched suits have stitching on both sides, neither of which break through to give water a path to follow.
     
  • Blindstitching (or double-blindstitching) is nearly always combined with a gluing-together of the seams beforehand, and protective tape for additional seal and comfort on the inside seams.
     
  • This type of seam is less durable than either overlock or flatlock. It is watertight, which makes a tremendous difference. Suits with this type of seam can have more paneling, meaning more flexibility, without causing more water inflow through the seams. The warm layer of insulating water near the skin stays there, instead of circulating with the cold ocean. Naturally, this type of seam is found on only the most expensive wetsuits.
     

• Arm/Leg/Neck Seals. This tends to fall under the 'fit' category. Most suits now have a wide, smooth seal at the neck. Make certain there's lots of Velcro to keep the neck closed.
   
• Closures.
   
  • Back-zip suits. The most common type, and for a long time the only type. Check these suits for a sturdy metal zipper rather than cheap plastic, and for good, thick flaps behind the zipper to prevent cold water flushes. "Zip cups" are often added in the better suits to the bottom portion of the zipper, providing extra protection against cold water intrusion.
     
  • Shoulder-zip suits. The major drawback of back-zip suits is the stiffness of the zipper, reducing paddling and surfing flexibility. Shoulder zippers eliminate this problem to some extent, creating new inflexibility in the upper chest region.
     
  • Zipper-free suits. These suits use new neoprene with more flexible nylon liners and various kinds of Velcro closures to create a suit that eliminates potential for cold water flushing into the zipper as well as flexibility problems.
     
  • These suits can be hard to get into or out of, are very expensive, and may have wear-and-tear problems. So far, few people have had these for more than a few months (as of early 1996).
     
• Thickness. Obviously, the thicker the suit, the colder the water you will be able to brave. Thick suits also result in more weight and less flexibility, as well as higher prices. Finding quality in the other categories can allow you to reduce the thickness for a given water temperature.
   
• Other Bells and Whistles
   
  • Titanium. A coating of titanium oxide is applied to the wetsuit rubber on the inner side of the suit before the nylon and neoprene are bonded. The titanium is supposed to reflect heat that is radiated out from the body. Does it work? In theory, yes, but it is unknown how important it is.
     
  • Polypropylene. Used as an inner lining for the newest wetsuits. This material is hydrophobic (repels water) and is supposed to help keep you drier. It is marketed both as used in the wetsuit itself and as a separate liner (like a rash guard). This stuff works best when just used totally by itself to protect from wind while surfing in warm water.
     
• Fit. This one is important. So much so, in fact, that many surfers are opting to pay $600+ for a custom-made wetsuit.