This is a relatively new restaurant, so I'm cutting some slack for a few things that are usually related to "growing pains" and will probably sort themselves out.
Residents of East Mesa are eager to have some nice dining options and I think Osteria has potential. We had the meatball appetizer (which was amazing) and the Pesto, Ravioli, bolognese, and salsiccia (mushroom pizza). All the food was really good. We did request a side of red sauce for the ravioli as it is not served with red sauce. You can taste that the food is made from scratch and everything was really good. The pizza could have used another minute to crisp the crust a bit more, but was flavorful and delicious. The wine list is fairly good and the bread and EVOO is good. We requested balsamic to go along with it and they accommodated our request.
The service on our second visit was better than the first. I would request that the servers not refer to me as honey or sweetie. Others might not overlook this as easily.
I hope that Osteria will continue to work out the kinks. This is a pricey restaurant for the east valley and although many EV residents are willing to pay for a nice dinner, they will expect great service and food. I'm hoping that Osteria will expand their limited menu to include a few more seafood and meat selections.