Fermented grey oolong tea tastes to me like fermented green tea. Considering that this is harvested when ripe, I would think it's similar. I don't like 100% green tea, but this was much milder and didn't have a strong green flavor. It was more like a light brown tea with a mild taste.
I came vacuum sealed, so it would stay fresh until you were ready to start using it. They also give you a clip so you can leave it in the bag it came in and re-seal it as needed.