Cooper Discoverer STT Pros vs KM3s
 

I'm just trying to figure out which tire would be best for my 2 door Wrangler. I use it for a daily driver and occasionally off-roading but no rock climbing at all. Mainly dirt, mud, sand, water.

Any particular reason you're limiting yourself to those two tires? If you're not mud bogging (or if you have a winch) the BFG KO2's are an awesome tire for dirt, sand, and water. I used mine like that for 50k miles with plenty of tread to spare. I made the switch last year back to Mickey Thompson tires and use the baja boss on my daily driver. I don't know about mileage, but there's a lot of rubber on them 21/32" to start with) and they weigh the same as the KO2. Weight is primarily what kept me away from the KM3.

the look and aggressiveness

Dick Cepek Extreme Country may be a good candidate for you then, it looks tough. There's also the sister tire of the Duratrac that's got barbed wire down the side, though I can't recall the name now. Kanati has some tires with beefy sidewalls. I guess what I'm driving at is there are more than just a couple of aggressive looking tires. Just be sure to check the weight of all of your contenders in addition to the tread depth when you're buying.

Cooper stt failure
 

Hello,
A 4 years old dated 19/19 stamped on tyres set of the cooper stt pro
on a highway at 50 mph rear left tyre just was falling apart
is this normal?
Can I address the manufacturer ?

https://cimg1.ibsrv.net/gimg/www.jk-...47683958b.jpeg
Was placed back on vehicle after tyres change
https://cimg2.ibsrv.net/gimg/www.jk-...c7a420bc3.jpeg
On situ
https://cimg4.ibsrv.net/gimg/www.jk-...1130f483e.jpeg