I'd disagree. I'm running a similar setup with a 965 and a 5870, and I run ultra details in WoW & SC2 at 1920x1200 resolution. (I'm guessing the difference between 5850 & 5870 is offset by 1920x1080 vs. 1920x1200...or my setup might be on the losing end of that battle.)
In WoW, I get 60+ fps pretty much everywhere except Dalaran and raids. Dalaran is usually around 30-35 fps at primetime, and raiding varies. 50-60 fps in 10s on certain fights, 40ish fps on really taxing fights in 10s. 25s are usually a little lower, but I don't raid 25 a whole lot, so I don't have a lot of data.
SC2, I'll admit that I haven't measured my fps, but I haven't noticed anything truly laggy.
Don't play any of the other games, so I can't comment on them specifically.
The 1055T might be better for overclocking, but that's always a gamble.
The Asus Crosshair III appears to be out of stock at newegg. Were you planning on ordering from somewhere else? If you plan on CrossFire in the future, the Gigabyte UD5 has about all the features you can ask for in an AM3 mobo at $180. If no CrossFire, the Asrock 870 sp12 mentioned is the cheapest fully-featured 870 board. There's also an Asus mobo for $5 more.
@ coldsleep ive already got my crosshair iii formula and i love it !!!
but what u said made me a happy camper cause i probably will be going with this setup and with what you said chances are ill like my results in games as far as graphic details go