I've had both, '12 and the'14. If the '12 is an early build then be cautious of engine issues... It may have a recall, not 100%, it may not even be a problem anymore. The cloth seats are more durable with the '14. I'd go '14, newer and less miles.
yes you can. by using a programmer like the superchips flashpaq/cal you can redo your shift points just by updating the correct tire size you have installed. the computer does it automatically.