I disagree if done RIGHT and purged correctly u can make high quality extracts leaving absolutely no traces of butane behind. 100%, it just takes patience. Butane is also hydrophophobic, so as long as your buds are properly dried and contain no moisture, you're only extracting the good stuff leaving undesirables behind. When water is present during extraction all the u desirable compounds are also extracted. Quality butane, leaves those u desireables behind which make for a much cleaner oil and smoother hits. Blasting with butane is how a lot of things we eat are made such as spices and cooking oils. It Just has to be done right