How durable is the fenix 6x pro compared to the sapphire version?

They are identical apart from the glass.

I thought the sapphire has DLC coating and the pro has PVD coating

I thought you meant mechanically ie the glass and the innards, rather than just cosmetically as the bezel coating adds nothing to the operation of the watch. I have a F6X sapphire, its great, I use it as a tool, and TBH I don't really care what the bezel looks like I just want to know that when I look at the watch I can see an accurate OS Grid reference and know that battery wont die for several days. And for battery life its just bloody amazing.

Of course everybody hates the first scratch, but whatever you do it will happen, eventually. 

Yeah I’m considering the 6x sapphire I made a mistake buying the non sapphire because I’m probably going to be quite harsh on it. However I want the bezel especially the glass to be durable so it can hold value down the road so I can make some money off it to help pay for the next fenix watch. And of course whatever on the screen to be visible and not blocked by scratches. 

well in that case get a screen and bezel protector if you are looking to resell it and don't bother with the sapphire. Every 6-12 months change the screen protector. In my case I cant be arsed to hide away a watch I paid for, I want to see it, if it gets scratched, so be it. I used to wear Casio watches when I went white water kayaking or surfing, and I have lost several, but they only cost £30+ so who cares, but hiking I love the features the F6x brings, battery life, maps, OS Grid references, compass, altimeter, barometer etc. The convenience of having it on your wrist as opposed to a dedicated GPS is amazing. I carry one of those as well (Oregon 750), but never turn it on, its just a backup. Cant be too careful :-).

The metal bezel protectors available at countless places have been a godsend for me. I've had the watch for about 6 months and one single adhesive protector has been all that I've needed so far. Even after countless swims, it manages to hang on. 

Glass is glass, sapphire is sapphire and metal is metal. I have the 6X Pro since a year without screen protector. I'h used Fenix 5X (sapphire) without protector and Fenix 3 with screen protector. None of them had an issue on their glass. However, bezel is easier to scratch and has nothing to do with the display being glass or sapphire. It gets scratched on both of them. However, scratces on Fenix 3 Silver were almost impossible to see as the bezel is the same color with the internal metal. However, on black/grey 5X and 6X Pro scratches show the metal under the coating and that's side effect of being black. 

Recently got a decent scratch on my Fenix 6X Sapphire that I only bought last January.  Ironically, it happened at work (I'm a RN) and not out in the field when I was mountain biking or lifting at the gym.  I had a Fenix 3 HR Sapphire for about 3 years and not a scratch on it...even after smashing it twice with a kettlebell when doing some overhead snatches lol.   Nevertheless, I still love this watch and it's not a big deal.  They're gonna have some wear and tear.  I was a little surprised how fast this one got scratched though.  

Remember what you scratch it on?

I think I bumped it against a piece of equipment at work.  We use a lot of equipment with metal handles and parts sticking out.  Super easy to hit it on random things.   I didn't think it would scratch so easily since my Fenix 3 was pristine right up until the day I sold it.   No biggie though.