I actually amended my order and went with this one in the end.
http://www.hotukdeals.com/deals/evga-supernova-550w-modular-80-gold-power-supply-scan-2556760

It's not fanless but at least it's noisy

Use fanless. After sometime the fan fails.

wa la =

modular = pointless

Same here. Although I think I'll have to stump up the extra as I don't want to continue running my £1k media server off of a Corsair CX430 anymore.

Thanks. It looks like the 550W EVGA SuperNOVA GS at £58 might be the best option then.
It's a bit more than I was planning to spend though

Use this list, anything from T1 or T2 and you will be good for 5+ years usually.

http://www.tomshardware.co.uk/forum/id-2547993/psu-tier-list.html

I was planning to use an OC'ed i7-6700k with it, but probably low-midrange GPU at the most so I probably won't be pushing it too much.
I see they have a decent price on the Corsair CX500 but not sure if it'd be a better choice?

Oh ffs. Now I gotta send this pos back.
Why does th GQ come up when I search for the 650BQ. Bloody Google. I should have spotted it but I'm still gonna blame Google.

As mentioned, that's a GQ review which are also fantastic and made by FSP, a very good PSU maker. Don't get me wrong, it's a good PSU, but not a great one and if you are putting quality parts with it, I'd always try and get a quality PSU.

EVGA GS, GQ, G2 and PS are all top quality full japanese capacitors, quiet, great temps, stable at load/oc etc i.e. all the bells and whistles. The EVGA BQ is mid range and not bad but don't confuse it with the ranges I mentioned, that's all. Like I said it's not a bad PSU, but if are building a quality system or have expensive parts, getting a quality PSU can make your PC last 5-10 years. I have never had a psu die on me (excluding the cheap PSU's I bought when starting to build 15 years ago!) and I've built around 30 systems in that time. Just my 2 cents.

That's the GQ, not the BQ

Terraheart: You have just made me consider cancelling my order.

It's a good price but EVGA BQ series aren't the best.

For those who don't know, only a handful of companies actually make PSU's, they then sell/ license them to other companies who reskin and sell them (monitor manufacturers do the same but that's for another day). That's what EVGA do and with this PSU they have taken a HEC (Compucase) PSU and slapped an EVGA label on it an wa la. The problem is HEC PSU's are only ok, they're a middling company that make average PSUs.

EVGA have a supernova G2 line, those PSU's are made by superflower and GS line made by Seasonic arguably the two best PSU manufacturers. Don't confuse all EVGA's as the same quality PSU's, like these ones which are in a lower league.

If you are making a computer that needs a 650w PSU (and most don't) then don't cheap out on it. Look for deals on quality PSU's, unfortunately this is not one. If you are thinking of getting it for a budget build, still, I'd recommend a quality 450-500w over this.