They were more gimmick then anything else.
KA #17 is still using them for some reason.
The first test of the GP12 had them on with bike 2, but not on the second test.
I'm glad to be honest. they looked stupid. Nothing new either, Heron Suzuki used them on the XR750B in 1982 / 3. They were rubbish then, still rubbish now.