Fioricet! Yeah, that's the one (couldn't remember the name). When I was first prescribed it, it was called Fiorinal, am quite sure that's the same thing in reading the info on it. I actually get a generic, butalbitol, now. I've found it most effective in the prodromal phase (which are usually quite recognizable after so many years). You probably already know, but be sure to take it with some food. Or oooooh, the burning... ugh. They also go "off" more readily than anything else I've ever taken (and smell vinegary when this happens). To prevent this from happening so much, I asked to have the prescription written for fewer. You have the migraines much more frequently though, so this may not come into play for you! (I have always found it interesting that it is indicated for tension headaches. Like you, I was prescribed it for migraines -- definitely migraines, not tension going on). But I've found it quite effective, especially as mentioned above, taken in the prodromal phase (so I always have some with me just in case). If I don't catch it then, it takes longer to knock out and more dosages.
Good luck with that, and let us know how it all goes!