Listen, I'm a newb and I'm here to tell you that I do not know what is best, but I have successfully transplanted two grows from soil to hydro while the plants were in early clone. I have a DIY bubble cloner that I placed the clones into for a week prior to putting them in rockwool and clay balls. They did excellently on both rounds. All I did was pH a pan of water (a little higher than your res will be pH'd longer down the road, because I didn't want to shock the higher pH'd soil roots too much) and very gently allowed the dirt from the roots slough away from them - I did not hose or yank dirt off of the plants. I did gently swirl the roots around to agitate the dirt clumps. I was able to clear almost all dirt off of every plant this way and it didn't take long. Then, like I said, I tossed 'em in a bubble cloner for a week and the roots went WILD on all plants, both rounds. Good luck.