I find the genetics of the seed you buy dictates the quality of smoke you will get - the quantity depends largely on how you grow it. Well ferted plants will have a larger yield than no ferts - plants grown under the sun will yield a lot more than those grown under little lights. And of course properly dried and cured bud tastes so much sweeter than wet bud that is rushed to the dealer.
To date in my "Gorilla Grow", thats not a "Medical Grow", I have growing the following, Super Silver Haze, White Widow, NY Diesel, Northern Lights, and Maui Waui. To date my most consistent would have to be Super Silver Haze, for size a vigor of growth. But all of those listed have stand outs. That is why if you have the time and space cloning is good, you can have killer what ever you grow, they all haver stand outs. Hey good luck with your grow.