See, it's like this - P. Cubensis is an organism that has found a very important new niche - people. It WANTS to grow for people, you can throw just about anything at it and it will grow, it wants you to eat it so that it can perpetuate itself. Look at it this way (Michael Pollen writes about this), Apples made their way from Iraq or Iran to the new world because they managed to make themselves appealing to the taste - and more importantly, because they were the perfect fruit to ferment - most apples are sour little things. Pot has managed to make it's way into places all over the globe where there isn't even any dirt - in garages, attics, basements and back yards - it has adapted so that it will multiply almost anywhere - with the help of humans, it is a realtively new symbiotic relationship. P. Cubensis has in the last 40 years discovered the fast train to true globalization. It used it's innate ability to affect humans and the internet to spread it's spores to places they never could have spread before.
No other mushroom has been able to manage this, most mushrooms, with the help of wind and animals can spread it's spores maybe a mile or two and it took millions of years to exploit every available microenvironment. Now those spores manage to travel thousands of miles. Now the mushroom grows in boxes in bedrooms all across the globe and it's spores are beginning, in places, to be a part of common dust everywhere in the U.S. at the very least. I have not grown cubensis for a very long time - and still, when I do contamination tests in my house I find a considerable count of them in my local atmosphere. I have seen it sprouting on the cheese in my fridge.
Stamets, when he goes on international foraging expiditions puts spore prints of his finds on his hat, in so doing he spreads those spores all over the globe.
The point of the two threads above mine are this - p. cubensis will grow using just about any tek you can imagine, all you have to do is give it a fighting chance over other molds or fungi and let it live long enough to fruit. In my opinion it is the easiest of all mushrooms to grow.
So have at it.