I've had a couple of mustangs. The first was a 2 yr old gelding I adopted. He was the easiest horse I ever started. I just took it slowly with him, but he 'joined up' after only a few days. I'd been riding about 40 years at that time, and I have to say that the first time he came to me and let me touch him was one of the most thrilling experiences I'd ever had. Even now I get a bit teary thinking of how brave he had to be to do that the first time, and how absolutly trusting he became. He turned out to be a fantastic trail horse - anyone could ride him anywhere. The other was a 6 year old mare that I never did get broke. She was just too wild and afraid. So, long story short - each is different, but if you've never started a horse before, you might not want to start with a wild one.