Tried it out last night. After a few hours with it, here's what I found that I don't like.
-No more titles at the top of the window. Sure, it took up space, but I'm not sure getting rid of it was the answer.
-F6 doesn't highlight the address bar anymore for whatever reason. I don't like Ctrl+L since I hit Ctrl+K sometimes by accident, which highlights the search bar.
-Text is slightly blurry due to hardware acceleration.
-There is NO ask for tab-saving upon closing the browser. I found a line change in about:config that fixed this, but what the hell?? WHY would you disable that by default?
Other than that, I can live with the changes. Any suggestions to fix this stuff?