The build is looking pretty good. One thing that I'm not crazy about is the PSU. That unit isn't even 80+ certified. You can get a modular 80+ certified PSU for cheaper since it has free shipping and a $10 promo code right now.
I'm guessing you're getting two of the RAM kits. If this is a gaming computer, you don't need more than 4GB of RAM. What are the intended uses of the computer? What resolution does your monitor run at? The $105 saved by going with 4GB of RAM would probably be better spent on upgrading to a 5870 if this is a gaming system.
You absolutely have no need for 8GB of RAM, then. Systems with over 4GB of RAM are really only suggested for people who are running very demanding, RAM intensive, programs like Photoshop, AutoCAD, etc... The 5850 will work good at your resolution. You might as well just put the $105 saved by going with 4GB of RAM in your pocket.