I had it done about a year ago on my face and leg and it was definitely not painless. They gave me a bunch of shots around my eye, both below and above, to anesthetize it and into my hairline. After you are good and numb then there is hardly any pain at all. I hate the cauterization they have to do to stop the bleeding also. You can smell your skin burning. Yuck. Other than that, a piece of cake. I was there about 2 hours. It all depends on how many slices they have to do. I also didn't have to go into the waiting room between each one because of where mine was located and was bleeding quite a bit.
MOHS is a procedure used for skin cancer that is on delicate areas like the face, neck, lips, ears, etc.