This question is difficult to answer, because taste is a personal preference. Here are some of the differences between black buckwheat tea and yellow buckwheat tea:

1. Color: black buckwheat tea is dark, dark brown or dark red, while yellow buckwheat tea is light yellow.

2. Taste: black buckwheat tea has a deep, rich flavor, some people may find the taste bitter. Yellow buckwheat tea is softer, sweeter, easy to taste.

3. Health effects: black buckwheat tea is rich in tea polyphenols and catechins, can help antioxidant, reduce the occurrence of cardiovascular disease. But it also contains caffeine, is not suitable for excessive consumption. Yellow buckwheat tea, on the other hand, contains more flavonoids, has a good antioxidant effect, helps prevent vascular disease and tumors and other diseases.

In summary, black buckwheat tea is a good choice if you like a strong and somewhat bitter taste and don't mind the presence of caffeine. If you want to enjoy a softer, sweeter taste and are sensitive to caffeine or don't want to consume too much, then yellow buckwheat tea may be more suitable for you. Whichever you choose, be careful to drink in moderation and not overdo it.