Is it worth going for a Radeon 7790 at this point (for £85)?

[Kantor]

This deal seems almost too good to pass up:

http://www.pixmania.co.uk/graphics-card/sapphire-technology-radeon-hd-7790-1gb-gddr5-pci-express-3-0-11210-00-20g/21323666-a.html?ectrans=1&gclid=CM6VzemE7rkCFY_KtAoduV8AmQ#srcid=11270&nopopup=1&merch=1

It's 20% off, and nobody else is selling it for any less than £95.

Some background: I previously had a Palit (ugh) GTX 460 SE, which seems to have been taken out by a failing PSU, a few months out of the warranty that I can't find and probably wouldn't want to redeem anyway because I would just get another 460 SE.

The 7790 is a step up, but it's not as good as the 7850 (about £30 more) or even the GTX 650 Ti Boost (but that seems absurdly large and I worry it wouldn't even fit in the case - there's about 37cm available from what I can see).

Is it worth going for the deal, waiting for something better, or doing something else?