Seems to me at the moment anything can be called CBD, and there are no standards. Also, the question is supply, and quantities. You can get pleasant stuff in the head shops for $100 that doesn't do anything except make you feel pleasant for a few minutes. On the other end, there's top of the line RSO for $40/g in dispensaries. Sometimes. Demand outstrips supply and the problem is reliability. Putting aside issues of standardisation and exactly what ingredients go in, it's not really advisable to start a course of treatment if you are not sure you will have sufficient meds for the whole course of the treatment (e.g. for the cancer treatment using RSO, you have to train up for a month with gradually titrated up doses till you hit a gram a day, then you need a gram a day for two months. No one can (legally) secure that kind of supply here in MI. Also, 1g RSO = 3.5g flower, for legal purposes and also that's what it takes to make 1g of RSO, and you are only allowed in my state to possess up to 2.5oz, enough for a 20 day supply. You can make it yourself, but again, it takes time, is not easy or cheap, and you run up against the possession limits. If you have a licensed caregiver, they could supply you the flower, maybe, but then of course, you have to make your oil with the skill of a professional. My impression of CBD is we are a long way off before it becomes actually practical for any but a small handfull of people. That said, it probably has a really good placebo effect for a lot of people.
------ 5 months follow up. I used CBD every day during radiation and it cured my gout. Also helped get through radiation. Not sure if it helped with the uptake of the radiation at all, but not sure it didn't, either. I'll wait till my next CT scan. But it's great stuff. I make my own cannabutter with hemp.