3:1 mainsheet length and diameter suggestions?

Can someone gives the length of their main sheet if they have a 3:1 system and if they prefer it over a two to one?

I use the 3:1... 5/16" is the diametere, and I think 65' is the length.  70' will be a little safer. I hate having even a couple of extra feet dangling for no good reason.
Here is the thing, if you have the 3:1 hardware setup, you can chage it to 2:1 in a matter of seconds.