I dont know anything about the superwhing that is not commonly known and have been posted on this forum. I do know that a die will wear out over time and that the later batches will have thicker walls. I would think that is the issue here? The superwings are made by Goodall and not the F16 class so we dont have complete control over them. <very reasonable amount of GBP> for a bare carbon tube from JohnP?? Whow, that is a good price. Unless you really want a wingmast or an alu mast, that sounds like a really good option. I dont think there is other reasons for not pointing you in the direction of Stealth Marine and JohnP than simply not thinking about it or not knowing the price. After your posts about the issue, I am certain others who ask about mast tubes will be informed about both options.
I dont know if there is anything else to say. I dont think there are two dies and would be surprised to hear otherwise. I dont think there is any ill will or hidden agendas behind the weight of the masts you and Gato got. Any advice supplied to you and Gato was surely all in the best meaning.