I'm also about to use them (fairly long types some 6.5cm in height). I'm aslo skeptical on this...why alfa didnt use something similar and uses always rubbers? did has to be something like thermal transfer to the carbs? more over, what is happening with all this weight ,alu mounts+carbs+ air box cowl + heavy original top cylindrical euro filter box? after all these, the carbs staying bracket -down to engine mount- must be used anyway? any ideas or experience?