Series device has errors! After a few hours engine damage!

We loved the quad-copter initially enthusiastic. We even bought a couple of replacement batteries to the flight time to renew.
The flight behavior was OK for the price. The audio and video quality of the built-in camera was rather poor, but it we put no value.

Unfortunately the Quadrokopter is (certainly not 10 hours) failed after a few hours of flight time as an engine has blown. Amazon has indeed paid the purchase price with no problems, but this does not change the lousy product quality.
PS: Who does not believe that there is a series defect, should we will see in the "Questions and Answers" here at Amazon. For several weeks now piling up asking for spare engines.

Conclusion:
Rather spend a little more money and buy a piece of equipment which is longer than a few days having fun.