I pulled out a bag of Hibiki-an Premium Sencha. Preheated the teapot (yes, also contrary to some people's opinion of 'correct' procedure), warmed the bowl and began brewing the tea. Wow. That 1st cup made me sit up and say, hmm good. I enjoyed it very much.
I think I can safely say now that using a yixing pot with Japanese greens poses no problems. I won't say it is better than Banko kyusu but there is no disappointment here and those who already have a good yixing pot should not hesitate using with sencha.
