I prefer gaiwan to everything else I have tried so far. It builds up the atmosphere, as you can pour more water once, twice, thrice... And get each time a bit different taste. Also, you get all out of the leaves. It is very general - at least among people I know - to make one huge mug of tea of a good quality leaves, then throw them away. Noo! Not so!
Besides, I consider gaiwan very easy to clean. I have separate strainer as well, but it's not so handy. Most often I just brew tea, green of black, as long as it takes me to drink it. Of course it gets a bit bitter, but usually I don't mind. If I do, I have second gaiwan, a little bit more spacious, where I brew the tea, then pour it into the one I drink it from.
I guess I'll like a small clay pot even more, but haven't had a chance to buy one so far. Well, it's good to have something to wait.