I've prepared an image with ImgBurn and just of curiosity compared two burned discs, one of which was burnt with ImgBurn, and the other - with Nero 6.6. The media, the burner, the reader and the DAO mode - they all were the same.
However, there is an exactly 2 seconds difference between two burnt discs. So I wonder if ImgBurn missed 2 seconds (leading gap?) or Nero wrote unnecessary data?
"ImgBurn 2.4.4.0, DAO"