I'm running a combination of 5625s & 5645s in all 7 of my r/c. There are people bashing those servos, but I have yet to have any problems with any of mine. I run an E-Maxx, Kyosho truck, MRX-3, and 4 touring cars. The few problems I had with other servos were quickly resolved by Hitec. I have to stand behind Hitec products and their customer service.