Have been up and down Africa (literally) on Cooper STTs on previous car - no problems at all. The Cooper LTZs get nothing but good reviews in the US (I'm yet to come across a bad review), Middle East and here - on and off-road. The Cooper STs are good in some conditions, but not the type you get in Australia - for that they made the Cooper STCs (same tread pattern, different compound).

Several people in the US use Cooper LTZs on their L322 Range Rovers, Sports, D3s, new Landcruisers etc. It isn't seen as a bad make - a bit cheaper than comparable Nitto tyres, but not much difference in the tyre itself.