My main reason for making oil with only leaves is because oi lasts a long time for me and i work a lot. Smoking it only lasts 4 to 6 hous depending on how much i smoke therefore i can regulate better. I have experience with oil but wven with my experience it makes it harder to guage as even a small dose will last long if i dont take it on a regular basis. Therefore small batches of oil will be better as i dont use much of it.