An Grá faoi Ghlas
This is a video series put out with Turas Teanga. They speak slowly, so everyone can easily understand. There's subtitles in Irish (though I suspect you'll find some with English ones, too).
It also showcases all three dialects, with one character having a thick Donegal one, and another using the Munster synthetic forms (though not super Munster - only Cheapas instead of Do cheapas).
Go raibh míle. Now that I've finished the tree, I'm looking for more immersive methods, and this works great. One question: Is this a show designed to be shown at schools? I'm only asking because the people seem to speak much slower than the hosts of, say, An Saol Ó Dheas on RnaG, and I'm curious if it's because some people speak slower than others or if it's intentional for the sake of understanding.