A good finish to good series.
Well, that was a pretty good ending, though I'd say the true climax of the series was the previous installment. Nevertheless, this final part neatly rounded off the Sonic Movie Madness story as well as linking the SMM story to Sonic and Other Madness 3, which is a nice touch. I enjoyed the references to Kill Bill and the brief cameos of the 'unused Sonic characters'. But it's truly a shame that you were unabale to fit those deleted scenes into this one because they're damn good. At least you've made them accessible though so we get to see them. :)
I've enjoyed the series, which has made a lot of progress and is still entertaining, no matter how much I watch it. I hope, therefore, that this will not be the last Sonic related flash movie you make.
Keep up the good work!