I've been taking it for a few months. You have to check the drug interactions. For example, I can't take Zyrtec (allergy med) or its generic counterparts with it on the same day.
For me, it clears up brain fog, but seems to work best if I take it about 5-6 hours after waking. Some days I feel like I have more energy, other days, I don't notice a difference.
I also notice, it's slightly easier for me to eat less and lose weight if I'm taking it regularly. Not by much, but it definitely helps.