I've been using 50/50. What's the best to use to extend the life of the coils? I get huge clouds with the 50/50 and am using a light colored juice. I get about a week out of a coil, could go longer but like a fresh coil. My friend had the same juice but 70vg/30pg and I found after the first hit it just does not seem to wick the best unless I let it sit a while.