First, let me position my tea drinking habit: I am a tea philistine. I like black tea, fairly dark, with a lot of milk and sugar. My needs and requirement are simple and unrefined. I just like the taste. I do not worry about whether the water is boiling, just under, or whatever temperature releases (or does not release) unattractive tannins. Whatever! For me the issue is simply: does the water turn dark enough and if I put a lot of milk in it, does it stay hot enough (but not too hot) to sip and enjoy immediately?
Like a baby gosling, I am imprinted on Twining's Earl Grey blend as my tea of choice, but I've been willing to branch out--Bigelow's English Teatime, Twining's Irish Breakfast & have even liked some loose teas: Red Blossom's Keemun and their Hunan Black are in my cupboard
So why do I think this Alfi is great? Well, in general, I make myself a pot in the morning & then drink it throughout the day. I used to have various tea cosies to fit various tea pots to try to keep it warm, etc. but by the third cup, I needed a microwave to warm it up. Yes, I have done it and lived to tell the tale. If you microwave with the milk in, you don't have to do it as long & usually it tastes OK to me.
I am not (alas) getting any kickbacks from Alfi on this. The information shared is solely to let you know about what I think is a great product that may meet your needs.