I recently ended up with a set of 4 Yokohama A539s, I say ended up because I had 4 Goodyear F1s put to one side for me but when I went to have them fitted they had c0cked up a little and fitted them to someone elses car (turns out it was a mate of mine so wasn't really that bothered - at least one of us got them!). I was going with F1s because I'd had a few sets on my last Cup, and on my Golf Anniversary, and they were great. Went with the Yokos because that's what they offered me (at a great price) and I needed the tyres there and then.
First week or so on the Yokos and they felt OK, but the steering was very light which gave the impression of a lack of grip and they didn't inspire confidence. However, I dropped the pressures by 3 psi all round the other day (was going to try loads of different pressures to see what worked) and now the tyres feel transformed. Good steering feel, good grip and seem very predictable when cornering hard. Another bonus is by the sounds of it they make a good track tyre.
So I can definately see me buying another set of these.