Got to be honest guys. I've been through 3-4 grows with rockwool and I'm starting my 5th. Not an expert by any means, but I have not had many problems. It is true that the Rockwool PH moves around a bit. Espeally the later you get in the grow. But it is not hard to control. Just messsure your run off, and make sure it is balanced with your res. Doesn't take long. I think I need to adjust my PH once every other day in the early delvelopment but more like twice a day in later stages. Could be a pain, but Rockwool has been good to me.

Just keep your eye on it.