Just pointing out one thing: The reviews where it has been shown that FX 8350 is providing 6 to 8 Frames lesser than i5 3470, testers did not use the highest image quality settings, little or no AA and little or no AF to make the games less GPU dependent and more CPU dependent. If you apply those, the gap becomes much shorter.
Also multi-threaded games like BF3 and Crysis 2, which also happened to be the two best looking games, the performance of FX 8350 and i5 3570K is almost same. Also don't forget that, the FPS was never lesser than 60 FPS which is more than okay.
regarding Stock cooler, in case of Intel processors, even you are using a non-K processor and gaming for long times, it is advised to get a after market cooler like Hyper TX3 for better cooling. Intel coolers are extremely bad and that's why they are not noisy.
Granted that AMD stock fans are noicy but their quality is far better than Intel Coolers. The current FX lineup comes with 3 Heatpipe based cooler withj solid copper base, resulting far better cooling performance, even for the hot Processor. You can go to 4.2 GHz stable with it. For that performance, the extra amount of noise it produces, is acceptable.
Regarding power consumption: If you run the FX 8350 24X7 for the whole month, you might get $10 extra bill and I don't think OP is gonna do the same.
Hitman4, the Motherboard you have chosen does not support SLI. Read the manufacturer's page for the product and check in SLI support is mentioned over there.