whoa! lol, rw cubes in ebb and flo is one of the most common and cool ways to go. Ok, i say cool becasue i am. Lol, it is easy and yes they do hold a lot of water so i water less. That makes it wasy. I am watering every three days now. I go one inch to an inch and a half up the cubes in a 3x3 tray. The rw is an excellent medium for roots an oxygen. Very stable.
However i cant figure out a way to do what you want to do. To jam them in is something i have not tried. I guess you could just sorta set them in the w\hole on 4 in cubes or 6 in cubes with hydroton aorund them. Wow, i just tohught of that never did before. The benfits of a forum! That might work. I will try with a clone, because aero and dwc cloning is cake and i am about to learn rw for the first time.
Or you could do hydroton or some other similiar fast drain and dry medium and flood every couple of hours. Those systems are more forgiving. I would do that i guess but i got a stockpile of rw and have read a ton so I am sticking with it.
i do know this, i have seen roots damaged and the tunting is a seriuos issue so with the rw cloning i am feeling safer about that. Your choice. i have never heard of transplant into cubes for aero, maybe if you layed them in. Some awkward time, you can imagine but i am kinda excited.