I like teavana, but as my friend mentioned "things don't taste the same at home." Because they have only recently started serving a single tea as a sample in the store. The default samples have 2 - 3 teas blended together!
There are a few blends I really like there, but the locations are pretty far for me in parts of the area I don't frequent, so I only make it a few times a year (20, 30, 50 miles away).
I love the white aryuvedic chai and the aztec fire at the moment. They are also a little pricey. There is a high quality tea shop about 1 mile from my house that I visit, and there is another premum tea shop nearby that makes teavana look cheap.
My default is Lupicia. They have a closer location to me, in a mall I frequent, since it is on top of a subway stop in the middle of downtown SF. They also have a second location near the Teavana, if I isit my friends on what feels like the other side of the world. I generally like Lupicia better, and they have a tea newsletter where they send out samples.
LUPICIA Fresh Tea (ok they only have 2 bay area stores, a socal store and one in hawaii.)