One of my friends bought an DJI S1000 that has now about 20 000$ worth of equipment in it. Starting from MÖVI M5 etc. As you can guess my friend did a lot of homework before the purchase. What came out of the homework he did was that theres no logic in the quality of DJI products. For an example DJI's A2 is supposed to be the highest-end of their products. But when you start googling about it and calling to people who have actually had experiences with it... some even say its worse than NazaV2 and most say its lot worse and unreliable than Wookong-M. DJI S800 is another story, the NON-EVO version likes to flip and crash because of the vibrations caused by the motor arms (should be fixed in EVO). The best alternative for DJI flight controllers is MK3.5... its old but nobody has anything bad to tell about it, other than the features that it lacks. But what would you rather have? Super reliable flight controller that will not be the cause of crash/fly-away or a flight controller packed with features but known for causing crashes. Even when money wasnt the issue, my friend went with Wookong-M as its known to be a reliable flight controller. As an owner of a Phantom 1 with Naza2 its only 1000-1500$ that I loose if it crashes. The risks involved in crashing are "minimal" compared to what happens wheny your S1000 with its carbon props comes down... But as said there are people who have experience with A2 and Naza2 saying that Naza is more reliable. Even though DJI isnt designing hardware for full sized aeroplanes, they are creating products that may contribute to accidents with huge multicopters etc. In my opinion some of the product development (eg. A2) tells me that they arent taking seriously their role on the market. Maximising the profit when developing products for anything thats flying through the air isnt the smartest way to go. From my point of view DJI creates the best products on paper, but the execution is lacking. Hopefully DJI will bring more reliable products for us in the future.