I had both a Single Fiber EMG(a needle is inserted into the muscle) and an RNS (Repetitive Nerve Stimulation) test 4 weeks ago.

The Single Fiber EMG was not as bad as I had anticipated. It was not painful, but it was *very* uncomfortable. To sum it up, it is absolutely NOT pleasant.

The RNS had no needles, just magnet like thingy's, and it was also very unpleasant but not "painful."

Hope that helps! :-D