Here we made the first test with a part of 15 mn from the movie Lord Of The Rings "The Fellowship Of The Ring".

We can see the size reached is respected. With GSPOT v.2.1, the analyze of the bitrate seems to respected: 929kbps.
Using Vitual Dub mod instead of Virtual Dub Classic seems to give some improvements, the speed increase of 10% for this kind of encoding.
Gordian knot get the second place with 43,11 frames encoded per second between XMPEG RC3 build 3 with 44,08 fps and FlasKMPEG 0.7.8.39 with 40,94 fps.