That's what I did with the 4 plants that are two weeks ahead of these guys and I'm not happy with it, I feel the roots are moving too slowly through the rockwool and I'd rather just remove it if possible.

Of course that could be because the medium I was using originally had no drainage and stayed wet under the surface for like a week straight before I re-mixed the soil and replanted, so maybe it's not the rockwool's fault, I was just wondering.