Flights

Your choice of nonstops is between Delta and ITA. Hmmm.

I recommend using Google Flights to search, and then booking with the airline directly. https://www.google.com/travel/flights

Is one airline better than the other.

ITA formerly was Alitalia. Fly Delta.

What's more important cost or timing? Do you prefer nonstops? I think you'll find good and bad stories for every airline. In March we flew Aer Lingus through Dublin to Rome. Our flight was cancelled for mechanical reasons and we had to reroute the next day, ended up flying from Boston to JFK to Dublin to Rome. It was a hassle, but besides losing one full day everything worked out in the end, and we're being fairly compensated. So, I personally would probably be willing to fly aer lingus through Dublin to Rome again, but I understand I'm giving up the convenience of nonstop. We booked our flights during Black Friday sales, and paid less than $500 each including carry on, check in bag and tickets that were creditable (if we cancelled, we would have gotten to apply purchase cost to another flight). In this case, for us, cost savings was worth the inconvenience, but it's personal preference.

We have always flown Delta and had good experiences. We just flew ATL to FCO direct, and it was a great flight with decent food, pleasant flight attendants, and good wi-fi & entertainment. I also liked leaving later and getting in later. It felt more natural to be up and landing at 5:30am vs 1 am EST. I privilege an itinerary over cost so long as I can afford it. On our return flight, we missed our connection in Charles de Gaul due to a Florence weather delay, and Delta let us have a better (later) flight the next day that gave us more time to see Paris. Next time, we'll fly direct home (out of FCO) as well.