Can anyone tell me about his bloodlines? Nitty gritty? Free running? Personal experience etc would be really helpful. 

I have a daughter.  She's huge, 16 hands.  Fantastic personality.  Long strided and naturally bendy. Not a bronc.

ASOF has so many offspring that I'm sure you can find one with every description from outlaw to super horse.

I have 2.  Both are 14 hands tall.  My mare is a solid 1D horse.  My gelding I just bought last August and will be futuriting him next year.  ASOF's are known to be quirky.  Depends on if you can live with the quirks or not.  My mare has some, but I can live with them.  Gritty-absolutely.  You either love them or you hate them.  I happen to love them.