I wouldn't use them on a copter or you might loose a perfectly good prop. The prop will survive the fall, but the rest of the copter?
Interesting. by "you might loose a perfectly good prop" do you mean that prop could go loose/escape during a flight?
Yea that's exactly what I mean. I was bench testing a small motor with the built in prop saver and it had a resonant vibration and when I gave it full throttle the thing flew off and all most hit my face. Something hit my ear, I think it was the little o-ring that held on the prop. I finally found it and it didn't break, it just came off from vibration and thrust. I wouldn't trust one.
Not prop savers, just look at all the expensive commercial units, not a prop saver to be seen.
They introduce vibration and make the entire experience more dodgy.
Hoping to put a camera on the quad. More vibrations would be a nightmare.
Started out bolting my props on and broke a ridiculous number. I've lost very few since switching to prop savers. My quad flies fine with them and I've yet to lose a prop in flight. Check the o-rings regularly and swap out any dodgy looking ones.
Which prop savers you are using? hobbyking?
Yep, just the ones that come with the motors I use: