I've had these on my f4i for about 2000 miles now and show no ware or tare. I used the old hairspray trick to stick them to the handle bars. If you are somebody who likes a smooth or soft grip these are not for you. They do not absorb much road vibration, but are super sticky.
This is my second set the first where wearing out after a year of hard use soft and stickie great grip for the money.
would give themn 5 stars if they lived a little longer
There have been no questions asked about the Driven Racing Skully Grips.