Hi Brit girl! This was one of the options my Doctors at the University of Iowa were looking at a couple of years ago. At that time it had a 33 1/3 success rate and they were a bit leary about it, however it is being done and their are hospitals that will do it.
U of I is a great hospital with one of the top Neurology clinics in the world. I have referred several people to them and they've either had a decrease in seizures or a complete stop.
I've had them for about 30 years now and the VNS is something that I am ready to do. It's something that will be talked about to my Doc. when I go up next month.
If you can, try to get an appointment with either Dr. St. Louis or Mark Granner. Their top of the line and I know you will be happy with what they can provide you.
Best of luck to you and i'd be happy to hear how it turned out!