You remind me of our first golden, Kezar who was so unhappy for at least two weeks after Maggie died then began to realize she was now the top dog. But she did cry when I let her sniff Maggie's collar. A real cry of pain and sadness. Both beautiful dogs. Miss my girls. We now have Harry and Hannah. Picture is after she went digging in the yard one day....Harry is right behind.
A friend of mine runs a land rover / range rover specialty repair shop. Based on his experience, they are capable of stopping anywhere, anytime, at any cost.
I don't know about the brakes, only their unreliability.