I don't know if this was mentioned earlier , but i strongly suggest staying away from the Hitec 5645 servos. Go all 7955's or save a little money and go with the 7985's.....they are both great servos. I have had 3 ( three!) 5645's fail on me. I have no idea why , but it seems like the gear train is extremely weak for some reason. It cost me one airplane , i saved the bird on the second time and the third one was caught before i took off for a flight. I had 5 of these total for a little 1.20 glow plane i had , i have 2 left , they still seem really smooth......but i will not use them. I have used the 5955's , 7955's and the 7985's and 5985's and had great luck with all of them. Some have close to a 100 flights and are still tight and smooth as silk. One more thing....the higher powered hitecs i have noticed , seem a little "notchy" for about the first 20 flights , until the get broke in. I'll actually spend some time with my airplane in the garage and work the servos back and forth for about a 1/2 hr ( while installed on the airplane , plugged in on the aircraft , using the radio.) to make sure everything is running smoothly , and break the servos in a little. It's also a good time before maiden flight to check your "amp draws" as well.....you could have 1 -2 servos binding slightly , which cause the RX batteries to drain quickly and you are straining the servo itself. Always check for binding servos!