For that budget, that build is almost ideal. There are a few changes you could implement, however. In this build, I added a higher quality PSU, and a aftermarket CPU cooler. You Still won't be able to voerclock, but your machine will be much quieter. I also added a higher quality case.
I'm going to have to agree with ragingh4vok on this one. The Sapphire card he has put in the build has a higher base clock than the MSI in the initial build, and aslo has the same cooling potential, all for 20 dollars less.
The XFX Power supplies are nice. I'm always a bit iffy when it comes to the CX series since they had some awful voltage ripple in the past.
The motherboard gives the ability to mildly overclock your system if you choose to do so. If not, it does have quite a few more expansion options than the Asus.
The only issue I can see with the build is the RAM. It would be preferrable to have a 1.5v kit for efficiency and compatibility. Check out the G.Skill Aries series.