Just wanted to throw in my 2 cents:
I'm using the Dunlop D404s on my bike. They are good but I'm not thrilled with them. I don't trust them as much as I've had some slippery moments out there. On smooth road surfaces, sometimes the bike will slip on tight turns. I can also spin my back tire rather easily on quick take-offs on smooth surface roads also. The grip just doesn't seem all that wonderful. I'm happy with the tire and it wears well but I think I'm going to try the IRC next and see what I think of those.
So far I've had Metz and now the 404's. We'll see about the IRC.