I also did a tiny upgrade on the helmet. Years ago when I got my TE2 Stormie lid from a US 501st member, he also included a set of solid welding lens next to the accurate flimsy acetate ones, so you can put up the one you like more. I had stored the green welding lens inside a big bin with all my parts and greeblies, but now I took it out and put it behind the acetate lens on the RS helmet.
This way if touching the lens they don't get pushed back in the helmet. I could have kept only the welding lenses, since you cannot tell there is a difference unless you touched them, but I preferred to have them both, the acetate on the outside for display and the solid plastic ones on the inside for toughness.
For the mannequin, using both lenses was my best choice - accidentally I pushed the acetate inside the helmet and I had to take the helmet off completely to fix the lens. Now if you look up front you see the acetate lenses, but behind them there is the welding ones that don't let the acetate be pushed inside.
