Terrible, where's the Trigun, the Cowboy Bebop...
"11mb?!" said I, this had better be the best collab ever! That's the problem with collabs, they are big, most times the music doesn't fit, and usually just consist of two characters facing off over and over again. They are also damn hard to review.
Some of those animations were really good. The author of the Samurai Champloo sequence ignored the limitations of flash, which may or may not have worked. I found it drawn beautifully, but animated not so well. Best sequence was Shaman King, it was fantastic, and proves that less is more. I don't even like Shaman King, but that looked very professional.
The others were alright, the first Vampire Hunter sequence was good, and the Dragon Ball sequence was simple again, which worked. Some didn't look fluid at all and they brought down the flash as a whole. Copy the author of Shaman King and try and make your flashes more simple. It's great to watch a character rushing at another and flipping out all over their face, but it's not so awesome if it's poorly drawn.
Finally, after my constructive criticism I deserve a rant... where the hell were Trigun and Cowboy Bebop?! You had Burst Angel, for crying out loud! I want classic anime! You had Evangelion, so I'll let this slide. End temper tantrum.