If you think the lighter fluid in a bic lighter is close to medically pure n-butane you need to go back to school before you attempt any sort of solvent extraction.
Edit: the point of my post being there is a huge difference between someone who shoves material in a tube sprays with canned...
As stated by someone else let's see real lab results. The highest testing extract I've ever seen test results for was BHO Johnson's entry to the secret cup in December. That was 92-93% cannabinoids.
Properly made BHO is where it's at. There is too much ignorance on the subject and it's the paitents that are effected the worst.
This thread is a perfect reason why I won't dab anything that wasn't made by me unless that person knows what they're talking about (which is very easy to tell)...