As far as the Maidana and Peterson fights go Khan started off looking a class apart, far faster, far more skilful etc. but as soon as he got clocked he seemed to slow right down to his opponents' level. He spent the rest of the fights taking a lot of punches. His defence isn't going to get any better at 147 and he's going to get hit a lot harder. I see him staying at 140 as llong as he can and if and when he does move up he'll be very carefully managed.