rapid rooters are better because they dont get waterlogged, what you do with rooters is keep a little water in the bottom of the tray theyre in, they are spongy enough to let as much air to the root area as is needed, while still keeping the cube fully saturated.
see the thing with rockwool is that they cant be wet at all. they have to be barely moist, or just damp. the thing to do is right befor you take cuttings, prepare the rockwool, just soak it with water, wait till its fully saturated, which shouldnt take long, and then what i did was take it into the bathroom and swing it toward my bath tub, to fling the excess water out of it, once there is no more water coming out when you swing it, its good to go, avoid watering the clones, just mist the plants and the dome theyre in, this will keep the rockwool moist but not wet, when its wet the cutting just drinks because water is right there, it doesnt need to send roots out to look for water. when its just damp, it knows there isnt enough water, so it will stop taking water up to make new growth, and revert the old growths energy to making new roots, to survive. so yea, thats just an important thing.