i been using vivi for a long time and i found that thick liquids like ry4 don't vape well with them,
so i use thinner ones like menthol, or apple, but that's a matter of taste,
if you have a variable voltage battery try 5v.
i changed to aspire bdc a couple of months ago, and found it gives
a much better taste on any liquids , and it looks like a vivi