I'll stick with TenFourFox/Aurorafox. All the webkit browsers are cool, but none of them have the ability to be customized like I have T4Fx/Aurora.
Speedial (not in to Top Sites where Safari chooses my speedials for me), Stylish, UserAgents, AdBlockPlus, AdBlockPlus with Element Hider (block elements of a page you don't want to see), LastPass, Yoono, Switchy (Profile Switcher), Viewmarks, RefControl, NoScript, RequestPolicy, website blocking; all addons I can't addon with WebKit, Safari or the WK browsers.
Sure there are workarounds, and Safari has some equivalent plugins, but for the most part - no. And while Glimmerblocker is great, AdBlockPlus beats it hands down.
I've made some optimizations of T4Fx/Aurora and they work for me. No, it's not quite as fast but I'm willing to sacrafice a small bit of speed for having the ability to use genuine Mozilla Firefox addons.
Webkit is great, and it's fast and I use it (and most of the other browsers) for specific purposes (Stainless for instance when I do need speed for something specific). Fluid is AWESOME! And Roccat has always been cool. But it just comes down to preference and most of the time for me, it's T4Fx/Aurora.