Hi Chris,
My daughters eye-teeth starting breaking through at approx 21 months. I had a similar experience as the other Mom's that responded, in that, these were some of the most painful to cut through for my daughter. She had no problem with her molars, but with her eye-teeth, she drulled (never had prior) and put whatever she could get her hands on in her mouth. The good news is, after the eye-teeth, this is it for awhile!
Good luck!
(Tip - my daughter loved to chew on a frozen piece of cooked corn on the cob - it really seemed to help her whenever she had teeth coming in)