Choosing between a straight or coiled leash usually involves the style of paddling you normally do. In the surf you want the board away from you. A straight leash at least as long as the board is so safe that you get pounded by waves. For touring and racing, the coiled leash keeps it out of the water and minimizes drag and keeps it close so you can quickly rejoin the race. A coiled leash is also great for general flat water paddling as well as a lot of tangles around your feet and other items. A straight leash is more traditional and therefore many are more comfortable with a straight SUP leash.
ALWAYS WEAR A LEASH, IT WILL SAVE YOUR LIFE.
For a SUP paddler of any level, on any body of water, it literally means the difference between life or death …
One of the worst things that can happen to you on the water is to be separated from your board. Not only is your board a PFD, it’s also an anti-hypothermia device that can keep you afloat and far more visible than if your in the water bobbing. The temptation for some paddlers may be to look at a calm lake and say “I do not need to leash here” but the fact of the matter is you should use them everywhere and all the time.
If you fall in and there is wind, current or even a breeze on a lake, or in the ocean, your board will catch the wind and literally sail away from you. Chasing your board, especially with a paddle in your hand, is a recipe for exhaustion.
Best bet in the event of leash failure (or if you see a paddler struggling to swim while holding a paddle) is to tell them to ditch the paddle and swim to the closest board (yours or their own) or (swim / float) to Safety Paddles are designed to float and can be retrieved once the paddler is safely back on their board.