I personally use oil for health reasons, I'm kind of restricted to it.
But for those of you who say you use butter because oil burns, the solution is simple; learn how to cook. Oil doesn't burn if YOU don't burn it. There's no automatic chemical reaction that makes oil spontaneously burn when you have the intention of making weed oil. Just lower the temperature guys, seriously.
I always have good results using oil when I'm using bud with it. I tried using hash in oil but I think I may have dosed it too low.
Going to make some more cookies today.
The only downside to oil that I see is that the number recipes seems limited, and treats often don't taste as good with oil, but you get over it eventually.