I've visited this place a few times and was rather disappointed by my last visit, but will try not to reflect that in my review.
Full marks for the tea; it is authentic, incredibly tasty (although it can be over-sweetened at times) and comes shipped from Taiwan. A half a lengthy menu's worth of hot and cold varieties of tea made my head spin the first couple times. As did the prices ($4-8). I have since discovered that one receives a pot of tea and servers will refill with water upon request for that price.
Food is above average and makes a visit rather reasonable with a combo including food and beverage ($10-12-ish to my recollection, although at my disappointing last visit, my combo hot drink came in a mug rather than the standard teapot which did come for my fellow diner's a-la-carte selection). A must-try is the shaved ice: despite the price, the toppings are plentiful and it easily serves 3-4.
Service is below average: I've had to ask the wait staff a number of times when one person at my table was left waiting for their tea when everyone else already had theirs and the you-must-flag-a-waiter-to-get-service system is in nearly full effect. I've only ever seen a line up on a Saturday night and the seating layout is not bad. I feel as though things are far more relaxed when seated at a booth, but it might just be the tea...
I do keep going back since it is reasonable for lunch and it is definitely not your standard lunch.