A good psu (650-750w) for up to £100

Hi, so my psu (ocz 850w) just failed and I need a new good decent psu. I'll go with any thing between 650-750w since 850 was already overkill. Does any one have any good suggestions? I was looking at the corsair hx750i which is a little bit over my budget, but they have a 7 year warranty. So I'm looking for something with good warranty and performance for that price. Any help appreciated.

EVGA 750W 80+ gold: http://www.scan.co.uk/products/750w-evga-supernova-g2-full-modular-80plus-gold-atx-psu

XFX 750W pro: http://www.amazon.co.uk/dp/B00B88Z314/?tag=pcp0f-21

Corsair RM750W: http://www.amazon.co.uk/dp/B00FG9FTDI/?tag=pcp0f-21

Seasonic S12G-650: http://www.amazon.co.uk/Seasonic-S12G-650-650W-Certified-Silent/dp/B00FW6EIIW