In regards to the job, sounds like there are lots of good reasons to take the new opportunity. In fact, from what you typed about it, sounds like it's an obvious choice that you have pretty much already made.

In regards to the house, without going into it, I have lots of personal and professional background as the basis of my opinion. Based on Salt Lake's status as a growth city right now, especially drawing more businesses from out of state, I suggest you keep your existing house and rent it out. That becomes a great long-term investment piece, and with the 3.6% interest rate will be one of the best decisions you'll ever make. Then buy another house in Salt Lake closer to the new job. Sounds like you weren't going to get anything from the existing house anyway, so I assume you have at least a small down payment to buy another house. FHA only requires 3.5%, and you'll get hit with lots of fees because of recent changes and since you're no longer a first time home buyer. 5% conventional loans are becoming easier to get and better for most again than FHA, and of course if you have 20% down payment saved up you're all set. 4.3% rate is still not going to hit you hard in the long run (not compared to the 5's+ we're headed to within a year or so...which is still very low by all historic standards).