Buying mushrooms illegally from a legit dealer in the US means making sure they have several uniform bags of the product. You want to make sure they're grown safely in a lab or farm. There are too many people who will go out and just pick mushrooms, which is incredibly unsafe.
Unless you're an actual mycologist, it's difficult to tell what's safe and what's toxic. There are even cases of mushrooms in the US that are toxic look exactly like an edible food variety in Asia; even down to identifying characteristics like spore prints. Entire families have gotten sick or even died as a result.
So from just a safety perspective this would be a good move. Humans used psychoactive substances for centuries, usually under the supervision of a shaman or some type of religious figure to undergo a journey. It's not so different than psychologist today looking to use mushrooms to treat serious mental conditions. We have the advantage today of knowing we're not really going on some kind of cosmic journey, but merely acknowledging how dependent we are on our minds giving us our rational view of the world; and seeing how that can be easily and radically changed.