but I'm getting some kits together for these. As the screens have large-ish slotted holes, I'm planning on adding in a larger diameter plain washer to fit next to the screen, then the o-ring, then ordinary washer and nyloc nut.
I used M4x12 Stainless Button Head screws nylon washers from an online model makers suppliers and held everything togeter with Nyloc nuts so I didn't over tighten. No Well Nuts, no drilling and no hassle. I even replaced all the ones on the fairing as well.
Same here - bought the pro-bolt Ducati kit in black and they're no different from the originals except they cost a hell of a lot less and you can buy different colours.
Just make sure you get the right kit. I ordered through Busters and they sent a generic 8-piece screen kit rather than the Ducati specific one (SKDUC9) I ordered. Probably best to order direct from Pro-Bolt: