I had a side by side comparison with the Imperial grade today, although I did not brew both the same way. One reason for that is the fact that I still don’t have two identical teapots. But I have also observed that the preparation I have come to use for the imperial grade doesn’t work quite as well for the premium grade. The latter responds better to a more agressive brewing, like a more standard gong fu style gaiwan brewing.
Anyway, I think I like the Imperial grade a bit more for its nuttier and more delicate nature. It is somehow more special. On the other hand, the premium grade is sweeter, more grassy and with more umami too. The taste is more in-your-face. The body is comparable and the astringency levels are similar too.
Flavors: Astringent, Grass, Nutty, Sweet, Umami, Vegetal