Ive been exposed to both during my time with tkd and I must say that the Chang style of sparring seems closer to my style(Counter fighter) though it was miles way from being a productive tool in developing self defense. It saddens me to see so many who feel that there sparring pratice doesnt resemble self defense as taught by there respective arts. I understand that there is certain boundaries, and that these act as constraints against the practitioners but this is something that must be worked past. At a beginner level these boundaries are a great thing but as one makes his journey into his art, it should grow and so should his ability to express that growth in a physical manner. This is on of the reasons, and a big one, that I feel that MMA training has surpassed that of the TMA. IMO
"When I let Go of who I am, I become who I might be."
Lao Tzu