Matt has described this as being like pixie dust, and I wholeheartedly agree. This is a beautiful tisane that brews up so sweet and tastes/smells like a sweet, fruity, photorealistic honey. The perfume or flavor is also quite similar to lychee fruits, which are related to longyan fruit, as far as I know. I have tried a honey from Mexico that was very fruity that tastes just like the Longyan flower brew does.
I wish I had watched Matt's livestream about brewing longyan flower earlier, as I accidentally overbrewed it the first time and ended up with a too-concentrated brew. But then I got the hang of it and was richly rewarded with the magical aroma of my remaining flowers.
Hopefully this will come back in stock next year. I would definitely like to try brewing a pinch together with another tea as Matt has suggested to add sweetness. And yes, it is expensive per gram, but it is worth trying even just once for the experience. I have not had a tea (or tisane) that is like this before, and I am sure it will delight many others.