Whelp, unfortunately, the BIOS update didn't do it. I still couldn't come out of sleep. I then unplugged all of my USB devices except my mouse and keyboard. That lets me get out of sleep once, but the second time I'm SOL. I tried to Hibernate instead, but the darn things hibernates and then restarts immediately.

So, I know the Gigabytes have this issue too as do the other Asus boards. Any X58 board that's working properly with sleep mode?