Wouter, in my opinion the snail works best for twin forestays. If you have a single forestay you must have the snail in front of the forestay and that means that most good things with the snail is converted to bad things (high windage and bad weight distribution).

I prefer to have the "snail" close to the mast to gain most advantages with the setup, and it is easy to reach in case something needs to be fixed. If something messes up with a snuffer you have more trouble accessing it when you are out on the water.

/hakan