Malcolm Gladwell had a marijuana article in The New Yorker last month. He detailed the need for rigorous scientific study of THC dosage and effects. Most claims of medical benefit are anecdotal, and many are contradictory. Older reports address marijuana that had far less THC than the modern plant. He asserts that we have no idea how legalizing pot will affect auto collisions, employment problems, and brain development.
I have never used it in any form, but live in Massachusetts, where it was legalized for medical use about 5 years ago, and for recreational use last year. The state has been impeding the process as much as it can, so the few medical dispensaries there are, so far, didn’t open till a couple of years ago. Licensing for recreational shops is slow, and the marijuana must first be tested by labs the accreditation of which is being delayed.