* I picked a color for IBM that was almost perfect (it barely darkened just a bit when I submitted), but it gave me a 3.14.
* Dropbox's logo is colored pretty differently depending on where it's displayed (I colored mine lighter, like the system tray icon, rather than darker like the logo on their homepage).
* For Apple, I tried just submitting without making any changes because it looked pretty close to correct already. I was given a 0%, even though it only barely changed.