Usually 10ml for me. if it's something I don't like, I usually put it on the "backup" list for when I'm running low on my favorite juices. They get me by until I get my new shipment, and I really haven't found a flavor I "hate" yet, just some I like less than others. After all, nothing in the vapor community can taste as bad as even the best cigarettes, unless it's cloves, which is an exception.