We tried Papa's on a whim one night while out walking in Port Credit, and it's become one of our favorite restaurants in the GTA. Friendly staff and great food that is consistently prepared correctly every time.
I'm a sucker for the pizzas - Calabrese and Tre Porcelini are my faves - while my wife loves the pasta (Nonna's with rapini FTW).
Papa's is a cozy little place, and sometimes there is a decent wait time to be seated. We'll usually arrive before 5 to beat the evening rush. They do not take reservations, although we've called ahead to see what the wait times are like.
Looking forward to the Burlington location to open!