Not aware of anyone from London round these parts but I dropped by TeaSmith last week as I had a few hours to kill between travel connections and was mightily impressed.
Set up looking more like a traditional whisky bar with gong-fu drainage built into the bar it was a very pleasant experience and nice to have a real life chat with someone who doesn't glaze over when tea talk veers away from milk and sugar.
Started off with a freebie of some overnight cold brewed silver needle, moved on to 10 or so brews of a super fresh Li Shan, shared some of Stephane Erler's 2003 Yiwu with the owner, got to sniff at some 70's sheng and left with a pouch of Dan Cong.
Along with the Dan Cong came a recommendation to put a few grams of the leaf into some good quality vodka overnight and then drink. Straight vodka is not something I can usually stomach, this time was quite different. Hopefully John, the owner, has tried my suggestion of a few drops of good quality tea in single malt whisky - the fun bit is matching the tea to the whisky.
The market it backs onto also has an great variety of quality food.
It's the only high end tea shop in the UK I'm aware of, long may it live.