straight from the horses mouth: racepace recommend the Nissan OEM belt. The Nismo one is apparantly too strong and in theory doesn't allow enough flex to account for expanion of the motor when it warms up. Good enough for me OEM belt it is.
Nissan OEM Belt is $86 + GST.
I'd take you up on the offer for the belt but i'm in Melb and much easier for me to just go to my local Nissan dealer. Thanks anyway.