I've taken a few Ryanair flights since moving to Dublin, and as such I've gotten to know T1 well.
This terminal is a good size, but not overwhelmingly big. If you fly Ryanair know the check in desks are at the opposite side of security. Similarly post security the Ryanair gates are the furthest from the main shopping/dining/duty. That's just Ryanair and one reason why they're (usually) so cheap.
But anyway the Terminal is laid out pretty well. Before security there is a McDonald's upstairs. There' a currency place, and a cafe on the arrivals level. The security is usually pretty quick, at least when I've gone.
The duty free store is a good size. I never buy anything (so I can't comment on pricing), but I like to browse around and smell some of the perfumes. Only day I'll have the money to buy Jo Malone's Orange Blossom. I mean I'd have the money if I stopped travelling, but I'm not going to do that.
There are a few restaurants and cafes after the Duty Free shop (and some closer to the boarding gates). I've had breakfast at Marquette (self serve style with an omelette bar) and lunch at Street Feast (on different occasions) and the foods been good.
If you've forgotten any shampoo or such the Boots post security has everything you need including a variety of travel size toiletries. As well post security you can purchase a bottle of water for a suggest €1, which is really reasonable (a lot better than the prices in the airport stores).
Bathrooms have been clean and there are several pre and post-security.
One gripe is with the Customs/Passport control. If you're not familiar any flight arriving from outside Ireland has to go through Customs/Passport Control. If you have an EU Passport it seems to go pretty fast. If you're non-EU like me (I'm from Canada and living in Dublin on a temporary visa) the queues for the non-EU passengers looks shorter, but always takes forever. There's only ever one officer working the non-EU line, so it can take a long time to get through. I know they're adding in electronic kiosks for the EU passengers so hopefully that'll free up another officer to help process the non-EU passengers. That being said the officers have been really friendly once I get up to the desk (and once I'm at the desk it takes me less than a minute).
All of the buses are a short walk outside the Terminal (you go through the lower level of a car park, which has a cafe and convenience store). I think the rental cars and another car park. I always take the bus or taxi.
Overall Dublin's Terminal 1 is pretty decent. I'm happy to fly into or out of there. read more