Stuff happens with airlines. Flights get canceled for instance. It's about how the airline responds afterwards that matters.
Well, flight got cancelled from from Venice to Philly with a connection in Dublin. Got rebooked on a flight the next day with 2 connections. Problem is, it didn't get rebooked correctly, and no one on the customer service could help. One person said to just relax and go with the flow. As a result, had to then get rebooked again for a flight for 2 days after that. Made it to the desk to collect boarding passes and an absolute curmudgeon of a human being refused to get boarding passes. Had to wait for another rep to arrive at a different desk to help. At least the flights went according to plan this time
Aer Lingus flights are cheap and so are their people. If you wanna risk it and save a buck, go for it. If you wanna put yourself in a better position then choose just about any other airline for international Travel. Does this mean that things wont go according to plan? No of course not. But if they don't, then be prepared to absolutely hate your life for the duration of the time it takes to figure out whatever issue is going on.