When I do use them 100-120 mls

still learning.  They tend to last till the first dry hit for me...

I have used rebuildables mostly - but am getting tired of re-wicking.  Plus some of the disposables I have used have given me really good flavor.

Depends on the flavorings and mix. The dark sugary dessert flavors tend to collect and caramelize on the coil and give that burnt taste much sooner than something "clean" like menthol flavoring where just a few drops will do ya. VG juice is thicker and tends to plug the wick sooner than PG. When too little juice gets through the wick it will "run lean" overheating and baking juice on the coil resulting in bad taste and dry hits so use a low ratio of VG for longer coil and wick life. You will still get "clouds" but nothing earth-shattering.