Elmers' Glue. Yeah, the white stuff we used in kindergarten. Does the same as RC-56 at a fraction of the cost. And when I need to remove the canopy for any reason, it comes off easier than if I had used RC-56. Never had a problem with any canopy blowing off with Elmers' glue either. Even the jets.
I honestly think that Elmers' glue and RC-56 are pretty much the same product.