I've been on every migraine drug available, my neurologist finally shrugged his shoulders one day and said "which one did you like best?" That's when I finally felt desperate enough to try acupuncture. A couple things I have learned about acupuncture:
1) I totally agree that its all about the practitioner, there is a lot of talent involved. I wouldn't go to just anyone, certainly not a chiropractor that also does acupuncture. Also, there are two variants of acupuncture, Chinese and Japanese. I totally prefer Japanese, the needles are smaller, you don't even feel them and the treatment is more subtle/gentle. But seriously shop around looking very closely at credentials, where they were trained, how long, what style, professional organizations they belong too, etc.
2) Acupuncture can definitely help calm down or even stop a migraine attack. However, what I've found is that it takes continuous routine treatments to really have an impact. When I started out, I went twice a week for about 3 months. Then I was gradually able to space out my treatments less often until now I can maintain good effect by going once every other week. If I have an attach in between I can go in for an additional treatment.
Acupuncture hasn't been a cure for me thats for sure, I still get migraines. But its been a big improvement for me. A better result than any of the medications I have been on and there are no drug side effects. I used to have migraines 4-5 days of every week. Now I get one about every 10 days and it is far more mild than they used to be.