We've read the "Renting a Car" section in Rick Steves' Ireland 2015 book and have some questions for the Travel Forum.
Is diesel fuel as readily available as non-leaded fuel in Ireland? Regardless, I've noticed that the rental companies charge more for a diesel car, even though the fuel is supposed to be cheaper.
Is a regular driver's license from the US all that is needed to drive in Ireland? The Aer Lingus rental car website said that an "international (driver's) license" was required but that term was not defined anywhere nor could I get hold of an actual human to ask.
After reading the challenges of people driving in Ireland, I think we're going to pay extra for an automatic transmission in our rental car to reduce one stressor of having to shift in unfamiliar circumstances.