Johnny to answer you, yea...the roots can become tangled together if you're working with more than one plant in an area. But if you keep the roots aerated you shouldnt have too much of a problem. I run a DWC right now and I've had roots that have gotten caught up with another plant with no problems. If you do get that or a root ball, juss submerge the roots in water and they're easier to work with as far as detangling goes. Peep my avatar, thas my DWC I have but my plants are a smidge bigger than that now lol I think that pic was taking Nov. 6th. I love the DWC because it keeps the roots aerated the whole time, even with the lights off thas why I can see mad growth from day to day. I need to replace an airstone cause one of them i believe has went bad, but when I do...its juss going to make things even better.
So if you are thinkin about doing it, go ahead. It doesnt hurt em unless you let it form a tight knit root ball. And im doing SOG with my grow too in the avatar