I think for a budget tyre the kumho 's are hard to beat ,not quite as good in the wet as they are in the dry,but unless you drive like ari vatenen i think you'll find them fine ,used kumho's for about eight years on various cars now and never had a prob
and only about £70 a corner too.
I like Kumhos too, had them on my 147s and they were really good. I run P Zero rosso and just bought one for £115 from my local tyre fitter. I know also that Kwik Fit's online deal is £117 per corner, which isn't a million miles away from your budget. I know the manual only lists P Zero Rosso and Michelin Pilot Sports for 18" rims but the michelins will be prohibitively expensive. I think ATS or Formula 1 have got a buy 4, get one free on which should bring the price down of a premium tyre. IMHO a set of discounted premium brand tyres for the same money as mid brand make a better buy - but that is just my opinion.
The only other point I'd make is that be sure what you're looking for. Pirellis are a soft tyre and they help the ride on the 18" rims. When I have run other tyres back to back with Pirellis just about every other make are harder, Michelins definitely, Bridgestones considerably so. Some of the less well known makes use hard compounds - which is good for longevity, not so good for grip, not so good for comfort.
If you get the chance to try something like your car with a set of tyres you're interested in fitted - take it with both hands. I tried a Mito 1.4 (95) Veloce with Michelins and then with Pirellis and I couldn't believe the difference - they really were like chalk and cheese.
146 1.6TS, 156 2.0TS, 156 1.8TS, 147 1.6TS, 147 2.0TS, 159 1.9JTS, 147 1.6TS, 159 1.9JTDm, Mito 1.4, GT, Giulietta 2.0JTDm, Giulietta 1.4tb, Giulietta 1.6JTDm........