Tough question to answer for me.... and the following is in regards to self made, not purchased.
I prefer the taste of BHO as I always find the QWISO has an 'after-taste' that I dislike while being 'slightly' harsh to MY throat & bronchs.
However, I prefer QWISO for its less volatile/risk process to us mainly 'backyarders'. **I don't work with butane ever in winter months or dry weather due to static/spark risk.
I prefer the consistency of BHO for handling & use, slightly sticky and cut able. Every QWISO I make is shatter & slightly darker in appearance (not necessarily a bad thing, just a preference).
I prefer BHO for less risk of chlorophyll extraction.... I'm allergic & is why I can't/couldn't 'smoke' doobs of bud (hash only).
I prefer BHO 'soaks' over spray, and if I had and wore a white lab coat... I'd feel all techy and all
I'm sure there's more, but my early morning migraine hazy brain is suffering near shutdown
