Hello Millsy,
I know your concerns... but my input: you are getting started, and you will have some accidents. My opinion is that you get a DJI clone.. or perhaps the actual DJI 550 kit. Do a google on "RM550 hexa".. make sure you notice the Version (V1 or V2). These are kits that the body plates have wiring already trace in them. All you have to do is solder them on.
Lots of the issues I have seens and experience. have been bad electrical contacts. If you are new, you may not have a video TX, gimbals.. etc.. so as long as you carefully read and do a checklist to check off. you may be surprise.
here is my checklist to help you get started if you do use the DJI 550 clone or not kit.
1. make sure your solder is solid.
2. Don't use the bullet connectors on the motors.. cut them off and solder them on directly to the ESC.. (be careful not to heat up ESC to much" You might want to solder this after you do step 6.
3. Tape as much wires, down and keep everything from floating around while in flight.
4. make sure to take baby steps.. I know when I first got started.. I just took it out and tried to lift it 1 ft to see it hover. DON'T do that.
5. verify wires again.
6. with props removed, put tape on them and when you power on, identify which motor is spinning which direction. Make sure it matchs your flight controller configuration.
7. if all is well. I would leave the rotors/probs off, then power the system and get it to idle, and try to tilt the hexa into a direction and take note if the motors try to spin faster or slower. This simulates it in ATTI or trying to level the hexa. (assuming you are going with a NAZA or WKM).
8. Double check your 8J config with the Flight controller again.
9. Double check the solder on the ESC and motors.
10. I would then go outside in clear area and have fun little by little.
I am sure there are lots more steps, but I item the things that were not in the manual that I wish I would have known. I have put props on incorrectly, I have had a bullet connector go bad, I have crashed on my first hexa maiden flight, I have had several crashes due to the bullets.
I have never had a DJI prop break yet. (though I think it depends on flight pattern and how you fly) I am the slow and safe flying. I do change the props after about 35 flights.. that is what I read and did not want to risk. Now, I have go to APC props. much more stable and seems to sound better.. not that I can hear any better.
I have never had a DJI motor go bad yet.
I have never had a ESC motor go bad yet.
How I figured this was just replacing my broken arms and I am still using the same motor and ESC.
This doesn't mean it will last, but just my experience.
As for the WKM software/firmware. I would recommend reading around. I have 3 WKM, and 1 NAZA. I had started out trying to update my WKM each time a new update came out. I learned it was fun till I spent most of my batteries trying to alter gains, and calibrating. I finally got each hexa flying as exceptable and now I am just spending my time enjoying it. I try to avoid the temptation of updating my firmware.. but I know there are both sides of view depends on you.
I hope this helps and enjoy your venture!
KS
ps.. forgot to add.. check your fail-safe settings....