I disagree about them falling apart or getting holes easily. I bought a screened AA t-shirt and while it feels flimsy (read: light) it still looks new after dozens of washes and has no holes or signs of wear. that's more than I can say for any other t-shirt I bought at the same time.
They run about a size smaller. I always wear medium, and that's what I bought. It fits ok, but a little tight. I wish I got a large.
And I have to agree, screenprinting on them is great.