Hay Dude, The instructions say that the struts are functional. I also did the coke bottle fix and it works great. However my Cub is usually used for introductory flights so I also glassed the wing center section. I cut the covering off two inches from the center of each wing. Then put six layers of ¾ oz. glass 3in wide over the center section and recovered with replacement fabric purchased from Tower.

Being used as a introductory flight plane I can say unequivocally that the glass eliminates the need for the struts. But it requires more time and money (just like any ARF).

Good Luck

Joe Felice