Like any other tire, alot depends on riding style etc...
The Portland Police Motor Cops use them here. I talked to one of them at a gathering (his personal ride is a gixxer 1k)
Here is HIS assesment:
6-9 K miles on a set
REALLY good rain tire (Oregon - DUH we get alot of rain)
They ride rather well and he says they are a good "heavy bike" tire and good all around tire. He says they can get a bit greasy if you run them hard on the track etc because they overheat easily. He notices they overheat and get a bit slippery when he is doing his "advanced high speed pursuit training courses" at the track.
Mind you, he is a SKILLED rider and this is on his police BMW.
Bottom line: Good tire for rain and all purpose.
Not recommended for prolonged HARD riding or track use.
More mileage than typical High Perf tires like Qualifiers , PP's or Super Corsas.