"If you can afford the weight, why not?  It can't hurt to have some protection on it.  I had my hand cut up pretty bad when my flight controller went crazy due to a short (not an APM - it was a custom board I was designing).…"

"Hi, Personally, learning to fly my quad very recently, I'd love to have protections for flip overs, for rough landings and even side landings ! I think it is very useful because of the number of props I am damaging in my learning curve. Here is…"

"I'm looking for a similar thing, so just checking back if anyone has found a good solution? For my case it isn't to save my hands or walls from propeller cuts, but I'm aiming to provide aerial inspection services (bridges, towers,…"

"Hey Alex, I used these to start with, they have protection so if you connect the power the wrong way round they won't short out anything on the output from the BEC. In fact they will take a reverse polarity connection for a really short period…"

"Hi, I did nothing."

"We have been wondering the same thing. What did you end up doing? How were the results?"

"Hey, I just saw your thread in DIYDrones (http://www.diydrones.com/forum/topics/hc-sr04-ultrasonic) and we have been wondering the same thing. What did you end up doing? Did you use HC-SR04 in the end? How were the results? Cheers."

"More on this topic on this thread (and probably a few others with 'EDF' in a search)."

"Shinji Uemura from the Japan ArduCopter group has also successfully built a ducted fan quad.    "

"Have you seen this? http://diydrones.com/profiles/blogs/ducted-fan-quadcopter"

"It would look good, and futuristic, but EDFs perform poorly at a stall/hover. Needs to be super light weight. You could probably reach an enormous altitude in no time, but the decent may be less than spectacular. A tricopter-like yaw control would…"

"I'd sure like to see someone try with these and report back!"

"Yes. You just have to attach them at some angle to create counter force to torque."

"I'm also not totally understanding what the issue is, how did it short out? Was it the power stage, or the controls stage of the ESC? Anyway, I have one of these servo testers, and it's really handy.  It can drive servos (or…"

"Alexandre,      ok, I would have thought those Turnigy would be as good as any..I've also used Turnigy's without issues although not that exact version.      I'm probaly missing your point a bit…"