Though the Sabertooth seems kind of.... meh. The Sabertooth is not a great value at all with the Asrock Extreme4 P67 sitting $60 below it. The Extreme4 performs to the level of the Sabertooth but still saves $60. Z68 is nice and all, but I don't really like that it is $20 more for a good Z68 mobo expecially when 16x/16x vs 8x/8x isn't a huge difference.
With the $60 saved you could probably getting a 90GB SSD (You should be sacrificing SATA III for more space). That way you don't really need smart cache. I recommend this guide. http://www.tomshardware.com/reviews/best-ssd-price-per-gb-ssd-performance,2942.html