Mixed bag with OCUK. I ordered 2 GTX 670's but they weren't suitable for my case - they accepted the RMA under DSR terms. No problems, plus free Haribos. That's not a privilege though, it's a consumer right (DSR, not the Haribos!).
However I mentioned on the forum I was ready to push the button on a Dell 30", and the blighters put the price up £50 very shortly afterwards (coincidental I ask you?!

). Lost my business that day as I had found it £30 cheaper than before their ninja price hike.
I don't think their prices are all that great on the big ticket items, but I still browse their selection and would use them again.