The 3rd board the AsRock 990fx killer more then likely will over heat before you get to 4.7ghz, although the other 2 should do just fine. The 1st board the AsRock Extreme9 is a steal for $145 after a mail in rebate right now.
Yeah I don't think in this case the Mobo is holding back that overclock any, so power delivery isn't a issue. I have heard good things about the Asus, but, it's blue, and well frankly it's ugly. The Asrock has good power deliver and crossfire/SLI support but, it only has 5 Sata 6GB ports. The Asus has 7 Sata ports and is a better make, will have better bios's, and is just a more refined product with the same features as the Asrock. If you can stand the look or don't have a case window I think you would be happier with the Asus. The Asrock 9 is a top of the line board, yes it's 150$ with a mail in rebate, but, you will never get that rebate. besides using that board, that's like hitting a fly with a sledgehammer; might be worth it for the lols but, it's overkill. If you ever want to upgrade your processor 9370, 9590 the Asrock 9 could be worthwhile, but, your 8350 is already at 4.7 so it would be a small upgrade.