FireFox. I could go into deep detail of why Chrome is sub-par, not by personal opinion, but based off fact. Though I'd rather save the minutes wasted on typing it.
I have always like Firefox. i have used Chrome a couple of times and it's nice but with this whole Google changing their privacy procedures, i'll pass on using their web browser.
Firefox for things that involve flash player, like gaming online or watching videos.
Chrome for casual websurfing that dosen't involve much flash content.
After somebody showed me their iStealer they had and saw how many Firefox passwords and info they had that's what made me change over to Chrome. It was hard at first but I managed to get the hang of it and I gotta say it feels like chrome runs smoother and faster and has some pretty cool stuff.