In my past life when I use to fly America West to Missouri to see my grandparents I always had a layover in Phoenix...well I don't know if you can call it a layover because I would have to run from one terminal to another...not much of a layover.
Flights to Phoenix itself is great (I fly United). Probably more so that it is such an easy flight from LAX but it is a pretty easy airport to get around and I have always had carry on only so I have never had to deal with baggage claim.