People invest in heady glass we find because they love and appreciate the art of glass. Glass is one of the toughest art mediums and can take decades to get good. Heady glass is made by highly skilled artists and are rarely ever replicated again.
If you find a blower you like, do research, like any investment you could lose. The artists have to be good, if not great, or at least up and coming. Will they inspire? Will they find their own path? If yes, they could be an artist to invest in.
When you invest in a piece of glass it is more for the function. Then when you invest in heady, it is more for the art.