Hey there,
I figured I would just share this with you and maybe, just maybe, it will help someone else.
A little background about me:
Diagnosed w/ CH about 10 yrs ago. Only once during the last ten yrs have I been out of a cycle ( for about 6 months) and that was about 4 yrs ago. On average, I was getting 2-3 CH a day... sometimes only 1 around 11:00 pm, sometimes 5-6 a day starting at 11:00 am and going every few hrs.
My neuro had me on Verap 80mgx2 twice a day and Topimax 25mgx2 twice a day.  I also take 500 mg of magnesium on my own twice a day.  This seemed to be what I was living with for quite awhile with the 2-3 average CH a day.  I kind of felt that "maybe tomorrow will be better".
This is when things changed.......
About 3 months ago on a Sat nite I started getting real bad... every 4hrs or so... O2 wasn't touching it, Imitrex, Zomig, nothing.  Sun AM, I went to the ER.  They gave me Dilaudid....2 hits.... nothing. The DR said I should be asleep..... didn't work.   Went home... in pain ready to blow my brains out.. For whatever reason, they finally subsided later Sun nite.  My Neuro was on vacation all week.  I went to a friend who is a DR., and he turned me onto to another Neuro, who actually wan'st taking any new patients, but took me as a favor to me, because I was so pitiful at this point, and to his friend.
After telling him what I was taking for meds, and the frequency of my CH's he said that NO ONE should have to suffer that much (something my regular DR never said to me) and that most people can prevent their HA's.  He said the dose of Verap I was taking was all wrong and immediately started me on extended release verap, instead of what I was taking, and at a higher dose.
So... He wanted me to start out on 120mg twice daily then keep bumping it up to as much as 480 twice daily....
he didnt have any use for topimax
What I ended up taking, and has been working for me is the following:
120mgx3 twice daily
topimax 25mg twice daily
magnesium 500 mg twice daily
If I remove or lower anything out of the equation, I get that funny feeling in my head............
Also..... I know I am NOT out of a cycle, because I attempted to try and have 2 beers last Sunday, with negative results 45 minutes later.
Hopefully this can help someone
Mark G.

I've generally had ok results with extended release too, it seems to suit some.  The other kind has a good track record for many and perhaps both kinds should be tried for results before verap is bypassed as a preventive med.