Kensek can I move into your loft?

So the only difference between the Gigabyte EX58 Extreme and the Gigabyte EX58-UD5 is the heatpipes and waterblock? Is there actually any difference between the two in terms of overclockability?

What is the SLI performance on the two boards like?

And are their any waterblocks available for the X58 chipset yet. I realise it doesn't really require it but if I wanted to watercool either board (and didn't want to use the bundled block with the Extreme,) are there any blocks that will fit this?