Cordyceps
I have friends who study Cordyceps in Tibet and the Amazon. Cordyceps naturally grows on underground buried insect larva, and the tiny above ground, fingerlike protusion (carpophore) is very rare and time consuming to collect. For that reason, any true Cordyceps from the wild is extremely expensive. The Tibetan variety recently got a lot of world press in magazine articles and also increased in popularity as more Chinese can afford it, so the price has sky rocketed.
Most cheaper alternative commercially grown Cordyceps is not from the surface fruiting bodies at all, but instead is an extract from the underground mycelium only. The surface mushroom is just the sexual apparatus of the larger, vast underground thread network which few ever see, called mycelium. So far no one has suceeded in growing the fruiting bodies since burying living insect larva is problematic and not cost efffective if possible at all. So rather than the hand picked Tibetan fingers, most commecial Cordyceps is grown on non insect substrates such as rice hulls, and then the mycelium is extracted and concentrated. Now whether these extracts from myecelium have the same benefits as the true surface fruiting bodies found in Tibet is in dispute.
I received a gift from an herbalist who has a company specializing in Chinese Herbs, of a small amount of Tibetan Cordyceps listed in his catalogue for $140! A quarter teaspoon in the morning was moderately stimulating, gave physical endurance that lasted hours and also instilled noticable sexual prowess. After I ran out of that, I bought commercial Cordyceps extract powder which was grown on rice hulls, and have to say it's effects pale in comparison, seems to do nothing for endurance, energy nor for sex. Who knows, maybe it is pure bunk. Never the less, I take a half teaspoon each morning.
I presume that the Cordyceps grown from natural insect larva substrate transforms some chemicals from within the insects into the fruiting body which then have unique medicinal properties that may not occur in rice hull grown Cordyceps mycelium.
For more reading Dan Winkler has good info online on his studies.
Reishi and Lion's Mane
Reishi has no particular subjective effect in me, but I trust the few thousand years of usage in Asia so I take a half teaspoon a day for benefits. Lion's Mane I can feel, it seems to feel somewhat like Piracetam, slightly sedative or even cloudy if I overdo it. Somewher it was mentioned it has uridine in it I believe.
I have friends who grow both Reishi and Lion's Mane, both are fairly easy to grow. Reishi is grown commercially indoors in clean rooms and Lion's Mane can be grown outdoors in humid cooler areas. Both prefer wood chips so are not problematic to grow like Cordyceps which needs insects to fruit. Paul Stamets has some good guide books if you re intereted in growing your own, and you can also find kits to grow Lion's Mane at home if you live in a temperate, moist region, it is fun to do and just requires water!