Holy wow .
All I can say about all those naysayers who were jumping all over you is that I'd bet not a single one of them has ever dealt with a horse that did anything more aggressive than maybe trying to bite or kick occasionally. Because they've never dealt with a truly dangerous, aggressive horse, they don't know how to deal with one.
I, for one, am glad that you are getting this opportunity now. You'll likely learn more from this 1 colt than you would from 100 easy ones.
I applaud your courage to stick with him and I am so proud of the progress you've made . I have to agree with Boots, that is one hell of a lucky horse to have ended up with you.