Ive got mine on at the moment...Im trying to "get ride of them". I only bought them cause they were the only tyre I could use in superlap back in July.
On the freeway at 110kms they are actually quite loud...
When they are cold also, they arent good, so drive as sedately as you can (as you should when everythings cold with the car! haha)
The only thing I can think they are really good with, as Nick said motorkhana's!