I agree with Chickenman
Actually, I've been using nearly only GordianKnot with DivX 3.11 or DivX 5.02. It produces quality movies with a filesize really close to the one I've choosen, in most of the cases.
I've been trying Vidomi also, but with XviD. Vidomi is attractive because it is a single software, while Gordianknot is using a little collection of softwares (it could be at its advantage because those softwares haev the reputation to be the best ones in their category, including Nandub that supports smart bitrate control for DivX 3.11, and virtualdub for Divx 5.02).
I like Vidomi too, with its nice and easy to use interface. But I go on using GordianKnot because I've never been disappointed by performances during encoding, options, and results