i dont like the cork ones tbh.

The rubber ones are great, they fit perfect with or without coilpack or even cam sensor setups like i fit, they can be cleaned easy in hot water with some soap and reused loads of times.

If using a cork one you must make sure that it has the metal inserts to stop you from doing them up too tight. Also you cant re use them if they have been on for a while.

Best off using the rubber ones.