I can't say enough good things about Postino. As far as locations go, I think Gilbert has the best food overall followed by Postino Arcadia and then Postino Central, but I would give all of them 5 stars except Postino Central which I gave 4 (due to freshness of ingredients).
If this is your first time trying Postino, you MUST try the bruschetta. It is out of this world. I've been to a couple of different other places that seem as if they are trying to copy Postino's bruschetta, but it is never as good.
Aside from the bruschetta, the salads are wonderful, all of them, my favorite being the italian picnic.
Most importantly, the wine is amazing at Postino. If you are not sure which to try, ALWAYS try the Postino exclusive. It will never let you down. All the locations except for Gilbert will let you take home an unfinished bottle which is really nice also. Even better, on Mondays and Tuesdays if you come at 8pm they have their special - any bottle of wine AND a tray of bruschetta! It cannot be beat!!