The plants all look like they are all doing well, and the roots look quite healthy also. Looks like you made the holes in the tubing just big enough to hold a 1 inch (or 1.5 inch rockwool cube in place. I like that idea, eliminating baskets and more
growing medium. The only thing I would be worried about is if it choked off the base of the plant if they grew wider than the hole. Any issues with that? Are the end caps removable for cleaning the inside of the tubes?