I tried xvid a few times (a recent build) and I found blockiness, usually when scenes change, as well as small white dots sometimes. I encoded one vid 3 times, the last time for 8 hours with all the "quality" features, and I could never find the end result suitable. For me, Divx was not only faster for a certain "acceptable" quality, but looked better too, with far less noticeable visual problems. I am willing to accept I'm new to it, but "out of the box" it is a lot more complex than DivX and didn't work as well for me. Audio, as always, I used the superior Ogg Vorbis, which I have nothing but love for.