I have played with my 3.0-3.2 clearos for a couple of days now -- haven't been able to go above 3.8 on my Buzz . I've pulled out all the inner rings and vaped; replaced only the "cup cap" ring leaving a little extra wicking room and vaped; I've" tipped" and vaped I've tried 85 PG, 70 PG, 60 PG and 85 VG and vaped all with the same results...burnt taste at anything higher than 3.8v, and/or if I take more than 2 draws in a row, and/or (heaven forbid) I take a deep, single drag...
The next step is fluffing / cutting wicks?? Getting lower ohms?? Using the 808s instead of the 510s??.
I've used 2.4-2.6 at 3.7v (as high V as I like), with 50/50 juice, cut the loops on the wicks and unraveled them a bit, wicks good and chain vaping, deep drags with nothing but flavor.