Like everyone else, I would take the later flight. Personally for my ex DUB I am overnighting for extra insurance (not even taking the last flight in the day, call me paranoid!)

On the return I booked a flight 2hrs after the BA from LHR is meant to get in... Given it's on time performance I also booked a flight 4 hours later as a backup (£10 for that measure of insurance as I am HBO)