We flew DUB>EWR in J last year on the A321 and throughly enjoyed it, the cabin crew were great. I'm sure the more frequent flyers may have a few concerns about the seat, especially travelling solo if you dont get one of the single seats, but we were more than happy with it. I do like transatlantic on single aisle aircraft (flew Jet Blue LGW>JFK the year before). We were staying right outside Penn for a couple of nights and the NJ transit from EWR was painless enough, not sure which I prefer versus the air train and LIRR to be honest. Having passed through JFK a few times in the last couple of weeks, it's not my favourite airport to be honest (lounge was ok though).