I never got the sugar I'm getting with the HD with the ro version. The ro version is def easier to dial ph wise but once you start dropping the HD to like 5.6 and hit your coco they put out much thicker stankier growth. I use HD now from soaking my propagation plugs at .2 ec to blowing em out in week 6 with 1.8 ec. Maybe it's that I'm recirculating, who knows. Keep doing what your doing.