I love the M8. Awesome radio. I've never used the 3d but I can say I've used some of Hitecs servos and I've had bad experiances with them. The two I've had wouldn't center for anything. Just didn't seem as high quality. When I was shopping for radios and was "trying them on" the Hitec felt cheap in my hand. Just didn't have the real solid feel that the M8 has.