Snowberry in 1-72 ? Looking good even after all this time, dust is a problem as is sun-light that will fade paint, I guess I am luck in the fact that I never really keep any, or many of my builds long enough to worry about dust, on the small side of things, I've gone over to something called acrylic gel, normally I'd paint the board that will have the gell spread across it, once dry this reflects a lot of light, after its dry, you can also mix (very very small amount) paint with a new batch and simply go over here and there, it looks okay, not perfect, but I like the results.