Ive been using time atac xs for a year now, brakeless fixed. Never had an accidental clip out unless doing a very sloppy whip skid where I rotated my ankle to the point of exiting normally. I managed to recover and continued. I used to use SPD's and had a few pull outs while skidding due to older springs and worn cleats. I dont think SPD's are as durable as ATACs. Stay on top of replacing cleats when they are getting worn and you should be fine. I hate riding with clip/strap set ups now, it feels to sloppy. Also a few times being able to quick kick out of clipless has saved me from taking a spill.