I'm a new member and this is actually my first post.
I know the OP was quite some time ago but I just wanted to give my 2 cents regarding the Evoke Potential as I just had mine today. I too have heard that some people can actually fall asleep during this procedure. Unfortunately, I wasn't one of those people.LOL. The left leg was very painful and it took me a few minutes before I could get control of the pain. The pain was enough to make me break out in a sweat but I treated it like labor pains (breathing and focusing on something else) and managed to get through without a problem.
I had a very supportive and encouraging tech who walked me through each step of the process. She advised me that the right leg would feel different than the left but she wouldn't know in which way until we proceeded. The right leg was definitely different, with far less pain, making it easy to relax through the rest of the test.
Just as an FYI, my setting was at 12 (I have skinny ankles) but she told me that most patients are between 30 and 50. She said she has in fact had some patients fall asleep during the procedure but she's also had some that could not tolerate it and demanded that it be stopped.
Everyone is different.