I have been a few times to this quirky little Dim Sum place.
The food is simple, but great - Dim Sum is the best.
Take a selection or leave your money with the waiter and he/she will see to it that you are happy when you leave.
The interior leaves a little to be desired and is great if you want to rediscover the 70s.
Wine is good and (cheapish for Oslo).
Service can be a little slack at times, but nothing to worry about - just relax.