I've ran nothing but cooper tyres for years, mutts nuts in my opinion.
I have STT's on my Offroad Disco/winch recovery machine, only struggled in the deepest of clag that no one else was moving in either, but once i'd dropped down from road pressure to 12 psi they bit through and pulled me out!
I run Cooper ATR on my road based Disco, they have coped with everything I have thrown at them including a couple of laning days around Nant y moch, Strata, Bomber lane etc.
I have recently had to replace my road based one after an arguement with a tree! And all 5 tyres are different patterns and tread depth so i'm going to replace, and it will definately be with cooper tyres.
The ST is a nice aggressive all terrain that performs well as well.