In any event - i have been reading your PSU guide. It is an excellent read, must have taken you a long time to write.
I think i have settled on a Corsair CX500. This was mentioned in your PSU guide, is it any good for an S1? No voltage drop/5v rail problems?
Only has 2 PCI-E which are both on the same cable rail, just go for the 750 and you double you PCI-Es.