Where is Mount Sinai?

Various theories for the location of Mount Sinai have been suggested. One is Jebel Al-Lawz in Saudi Arabia, which was in Moses's time part of Midian. The most popular location is in the south of the peninsula of Sinai at either Jabal Musa or Jabal St Catherine. St Catherine is the higher of these two peaks. What is the evidence for any of these, or any other, mountain peaks?