to get the most nic absorbtion from vaping requiers a diff technique, as the vapor particals are much larger then the smoke from an analog. take long slow drags roughly 5-7 secs hold it in you mouth for a sec or two and then inhale... and exhale slowly thru the nose. as the nic absorbs into the mucus walls easier than in the lungs. also try getting the highest level of nic content in your juices. the highest ive seen is 36mg.
the best steup imho for ease of use and reliability would be an ego-c / and or the ego-c twist (if your looking for vv) along with a LR DCT(low resistance dual coil cartomizer tank)