Don't go for AM3+, even when budget is tight. Also, don't listen to people saying otherwise, that intel is expensive and amd is for budget builders.
You can simply go with Intel based machine without even exceeding your budget. Also, that could proof you for future upgrades on already existing CPU's (get the pentium g3258 and in the future buy an i5/ i7 4th generation).
The am3+ socket is dying, and with that it takes the FX chips together. Just buy intel, don't make the mistake of listening to people online (hahah ironically listening to me). Just buy quality, rather than quantity.
But to answer your question, the 970A SLI krait edition from MSI seems rather promising since it comes from a brand of a higher quality than Asrock.
ASROCK:
more ram capacity
better ram overclock (can reach higher), however poor base clock (base set at 1333Mhz)
better audio Realtek
Looks sexy
MSI:
Costs less
Same north bridge and south bridge
Same power phase
I'd still pick MSI because it's black and white design, and cost less for the same overclocking capacities.