whats up man.
although I do not use the SOG method, my buddy does and he uses the same combo as I do. root the cuttings/seeds in rockwool (little guys 1" i think) and once the roots show is when i stick them in my 3" net pots with hydroton. cheap for sure since you can reuse the hydroton. The root growth seems to be a little better when the medium is mostly the hydroton for me anyways. I am a newbie myself and this is what I have been doing and has worked well. best of luck. peace