Ive topped before when I was growing for fun. I was successful keeping it nice and filled out without any problems really...but then again I didnt harvest anything back then....i wish I still had my old pics. They on my exs desktop and she gave that to her dad and he wiped the hard drive... i was basically growing a hedge at one point like 2ft tall and 3ft wide when i chopped it down. That was a grow I was gonna try to harvest but my home made stealth box had a critical failure....the lights fell on all 6 plants only that one survived....it was a male bushier than hell tho