I've always used Kumho Ecsta Supra 712s - recommended to me by Callum Lockie and always been a pretty reasonable compromise - cheap and ok grip and ok-ish on track both wet and dry (but I don't hoon).
I've always used Micheldever tyres (01962-774-437), either gone down there and had them fitted or got them to deliver to my local fitter - prices have always been rock-bottom.
http://www.micheldever.co.uk/
Fox
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Not in league with Micheldever, own shares etc. etc.