Also flew Edinburgh to Dublin on smaller Airbus during same trip.
Flight from Boston to Dublin only took 5 hours! Amazing!
Transatlantic flights seated in exit rows, amazing amount of room. I'm 6ft (183 cm) tall, around 260 pounds (113-ish kg) , was thrilled with the amount of legroom in my exit row, aisle seats. If it helps other larger passengers, I did not require a seat belt extension, and had plenty of room left in the belt. I carry most of my extra weight in my stomach/upper body. (apple shaped.)
The cabin crew on all of my flights were friendly and attentive. I ordered low-sodium meals, which included a chicken and rice based main on both. Main was ok, but I was quite happy to be served several nice fruit salads on my flights. The meals passengers around me were eating all looked and smelled nice for food served in the air, especially for economy flights.
On the short flight from Edinburgh to Dublin, the seats were very comfortable. A cushier leather type sadly not found on the transatlantic service. The entire plane is economy for these short hops. I was seated near the front, which was nice, and again had plenty of legroom in a typical 3 and 3 configuration, standard exit row seat. I also did not require a seatbelt extension for this flight
This was my first time flying Aer Lingus, and I would happily travel with them in the future.