MP uses hemp CBD products! (And I borrow it sometimes!)
I do think it definitely works to chill out dogs (and humans)! I know that MP and I both sleep super soundly when we take it at night, and she gives less shits in general when I give her some before a likely-stressful event (say, a get together at a friend's house).
We use it for seizures and for pain relief—I am not sure if it does anything for pain, but it seems to help with seizures somewhat. The brands I've used are Canna-Pet (oil, capsules, cookies) and Endoca (oil), and am going to try the Canna Companion capsules when they come back in stock, because my vet friend met the owner of CC and was thoroughly impressed and recommended them. For our purposes, I think I've been giving too little, so am scheduling a free consult with a vet at Canna Companion. The companies that sell this stuff have been super amazing at providing ongoing help re: dosage, timing, etc. The good thing about hemp CBD is that you can't really hurt them if you give more than indicated—they just sleep it off. I gave MP too much oil a the very beginning (the dropper kind of sucks for control) and she just Zzzzzzz-ed super great for a few hours.
Speaking of dosage, I got the Endoca oils last time because Canna Pet products don't have a guarantee for how much CBD is in their products, while the Endoca oils contain 1 mg per drop. One good thing about Canna-Pet is that it's made for animals by vets (but ppl can take them), and (not sure if that is the reason, but...) their oil tastes a billion times better than the Endoca kinds made for humans.
I would do oils if you want quicker effects (w/in hour) for a limited time; capsules if you want to sustain the effect for several hours. MP has been getting capsules with breakfast and dinner, and oils during the day as needed, along with a few drops before bedtime.
If I were in CA, I'd love to try the VET CBD that's made with MJ instead of hemp!!!! They won't sell out of state because it's pot, but hemp CBD can be bought/shipped anywhere. There's probably a Colorado based one similar to VET CBD, but that one is kind of a well-known one. I seriously thought about driving out there to get it, or have a visitor bring her some. (MN has medical MJ so it's fine to have it here.)