Used it once and will definitely use it again. As you say you book and pay online, you give an idea of your arrival and departure times, you are given a code via text, use that code when you arrive at the barrier to open it, you are directed to a free place, a bus comes every five minutes and you are in the terminal within five minutes. Brilliant. You don't travel around north Dublin for twenty minutes like the other long term/holiday car park. On the way back hop into the bus, short delay, get to your car (remember to take note of where you park), go to the barrier exit and just after you exit you get a text thanking you for your custom. That's using technology!!!!