I don't understand some companies, where I used to work, if we got a graphics card back, we tested it, if it didnt' work and it hadn't obviously been mangled by the customer(sometimes they are, and its obvious, like a MSI mobo where someone used the wrong usb plugs in the wrong ports and the board had obviously been on fire for some time by the state of it

) we'd simply replace out of stock, send the faulty card off, get a new one back, stick the new one back in stock, jobs a goodun.
VERY rarely do companies send repaired products back, its simply not worth the time or effort. The increased speed in turn around for the customer means that person will more likely continue to shop with you in the future.
OCUK should do the same, test, and replace out of stock. Obviously thats an issue with older cards and things out of stock, but who can blame them at that point.
Two stores, one was OCUK, RMA'd mobo's that were out of stock and the "previous gen" chipsets, both occasions I e-mailed and asked if they could simply replace out of stock with an equivilent new board(ie same priced by the new chipset). Both times I waited , i think 2-3 weeks for OCUK and 6 weeks for a Manchester based competitor, just to have them ship a board from stock when the respective companies told them they didn't have any boards to replace it with. Both times I could have been sent the board the next day after testing, no idea why companies don't do it.
I now mostly buy from two companies who "most" of the time replace out of stock if I have problems without the painful month wait missing a mobo/gpu/memory/whatever.
EDIT:_ SOrry meant to say that thats exactly what their priority RMA sounds like and what I'd have expected in terms of service had I bought that card, even more so if I bought from OCUK over somewhere else especially for the RMA.