Well while I was waiting for a reply from Hi tec I phoned Great hobbies and talked to the Tec dept and they assured me that there was no issues with the karb gears and they were safe to use on my 1/4 scale planes gas or not...He read the box to me over the phone where it says they are four times stronger than conventional white resein gears, and they are less likely to strip under the shock and loads that would usually break standard gears..However when I finally got an Email back from Hi tec they confirmed what you said about the use in gassers...I have sent them another question asking what they recomend as a replacment servo ..One that will bolt in with out having to change anything...Or if there is replacement metal gears...Thankyou very much for the heads up on this...