Hi guys just chiming in... I upgraded SL from a vanilla Leo install. I cheated though, booting and installing it with a USB>SATA adapter in my Macbook. I also used digital dreamers X58 mobo script for Leo and the kexts/dsdt on this thread for SL. Also I'm using the 0904 BIOS and getting like 11000+ points in Geekbench 64 when OC'd to 3.4 GHz