As far as the commute, it really depends on the exact locations of your Point A and your Point B.
If you decided to live in historic downtown St. Augustine and your job was in downtown Jacksonville, you would have a beast of a commute. If you lived out on Anastasia Island, it would be even worse.
But if you lived in the northernmost part of St. John's
county, and not really in St. Augustine
proper, then that would be a more bearable, though still lengthy, commute. But then you're also a good distance from the sights of St. Augustine - you're kind of halfway between the 2 cities of St. Aug and Jax.
We just had a similar thread, here's a link to some of the responses there (including my own lengthy response

):
http://www.city-data.com/forum/jacks...augustine.html