New PSU, scare stories have me... well, scared.

Hello all, many a time i have happened across tom's hardware when frantically scouring google for various problems i've had in the past. But for once i thought i'd ask you fine folks straight up.

Soon (payday) i'll be getting a new case and cpu cooler [xigmatek midgard 2 & be quiet! dark rock pro 2, respectively] and I've thought "to hell with it" and am seriously thinking of getting a modular PSU (my current PSU is an atrocious mess of multicolour wiring), a quick browse of scan and i've limited it to two options (although, of course, i'm open to suggestions).

One of them is the Corsair HX650 and the other the Seasonic X-650. Both seem great, but a quick google search makes it seem like PSU shopping is at best a mixed bag of results. Many people who went for the corsair, for example, experienced either DOA units or the quite frankly spectacularly weird "bird call" fan noise
The Seasonic seems to have frustrated a number of customers also (DOA units etc), although mainly for their poor customer service.

I'd like to think that these are extremely rare cases, and whichever i choose would probably work just fine. But i'm the kind of guy who could walk through a field of flowers and come out smelling of sh*t! And if i'm going to throw £100 at a PSU, i want a near guarantee that it will work as intended.

Any info/suggestions/general comments would be greatly appreciated!

Thanks,
David

P.S. For anyone interested here are my specs:

Gigabyte GA-Z77-D3H
i5 3570k w/ arctic freezer 7 pro
8gb kingston HyperX Genesis XMP
EVGA GTX 460 1GB (next on the upgrade list)
Arctic Power 700W PSU (works fine, but gets a little hot and is moderately noisy, plus aforementioned disgusta-wires)