Agreed with the above poster. He looks very strung out in the trotting picture. Personally I don't mind if people begin jumping horses at a young age, pending on the growth and devlopment of the horse. I small jump here and there "shouldnt" hurt them. I never liked young thoroughbreds. I find I personally don't have the patience to deal with a more than likely high energy young and green horse.
Go and visit him. Ask someone to ride him and watch him carefully. Than ride yourself and see how you like it. It all depends on what you are looking for in a horse, and what you know you can handle.
A Dog looks up to a man,
A cat looks down on a man,
But a patient horse looks a man in the eye and sees him as an equal