Yes, a lot of people find that neurontin has fewer side effects than tegretol. (I've read and posted on the Trigeminal Neuralgia forum off and on for years under different names.) I outlined my medication history in a poem, actually, which can be seen here:
http://neurotalk.psychcentral.com/thread101428.html

My pain started at age 14, but I wasn't properly diagnosed until 19. Of everything I've taken, Carbatrol (which is just extended release Tegretol) was most effective in taking away the pain. Side effects were more severe, but I adjusted to a certain extent. I did sleep walk while on it, though. Also, it interferes with hormonal birth control, and I got married a few years ago, so I switched back to neurontin.

My periods of remission and exacerbation are pretty closely related to three things:stress, allergies, and colds. The first two especially. I moved twice in high school, and didn't care for school, so I spent most of each school year in pain. However, once I got to college, I was much happier, and even spent nearly all of my freshman year in remission.

Throughout college I spent much more time in remission, though I typically had exacerbations for a few weeks around finals, and a few weeks mid-spring semester from pollen and such. Except for one of those times, I was able to control the pain completely with medication. (Sophomore year of college I finally got neurontin and tegretol.)

I spent August 07 - May 09 in graduate school. I spent probably 9 months total not in remission spread out over that time period. I was always able to control it with pretty low doses of neurontin (usually 600 mg)

However, this past August, it came out of remission (I'd been fine since April) and it was the worst it's been since I was in high school. I wound up on 1800 mg of neurontin, like you, and have dealt with pretty bad nausea this time around. I did try lyrica for a while, but it actually made the pain worse! Anyway, since late October, I started tapering off my neurontin and was down to 300 mg (YAY!) but have bumped back up to 600 mg. We'll see what happens. I'd really like to spend the holidays in remission.

I think that some of the Trigeminal Neuralgia folk take neurontin and tegretol together. It might be worth talking to you neurologist about.

Do your pain attacks every cause you to cough? Mine do, and sometimes to the point that I throw up. Fortunately, that doesn't happen very often.

I've had speaking as a trigger for a long time, and know what you mean about sometimes not being able to talk through them. I did have a new trigger this time around though. Simply bending over to pick something up on the floor (putting my head below my heart, essentially) would trigger an attack. It was pretty annoying.

I also have pain on my left hand side, but have never had an MRI to check for vascular compression of the cranial nerve. Brain surgery seems pretty extreme, especially when I can get meds to work. I don't think it's a compression in my brain, though I do think there is sometimes a compression somewhere, because occasionally I get this annoying throbbing when my nerve is extra sensitive. I'm not sure how to describe it, exactly.

I've always found drinking to be more dangerous than eating. How about you? I've also noticed that more acidic drinks are more likely to trigger an attack. (ie, water is better than soda, milk is better than water.)

How about you? My husband has just really gotten acquainted with the foibles of this... disease? this time around, and I've never really had anyone to compare notes with. I'm sorry this is so long. Like you, I'm also doing a brain dump.