Since I changed from Windows to OS X I'm going the opposite way: I changed the tab close button in Firefox and other applications (if possible) to the left side, to match the general appearance of OS X. It's only a matter of habituation, but each to his own...as you mentioned.
I can confirm to that.
Youtube, flash based movies on tubmlr.com, androidnext.de, heise.de feel like a dia-show when played in fullscreen.
If I use chrome with the same URL the video plays normal.
You can even feel the lag on facebook playing a game. Once it is fullscreen, there is a visible lag in most animations. If you have a page full of flash-ads (happens quite often, if you don't use an ad-blocker) it like the animations are "stuttering". If you open the same page in Chrome, they are displayed fluidly.
Betriebssystem: Windows 7 64-bit (WoW64)