We went with a group of friends in the Christmas and New Years break.
Positives.....the food is the best Vietnamese I've eaten since holiday in Vietnam. It was lacking the addition of the fresh herbs you get in Vietnam, but otherwise flavours were delicately balanced, the quality of ingredients high, and serving sizes just right. The Hanoi Hunger gets you a taste of 8 dishes, which is great. They also have many gluten free options which is good.
Service was great, prompt and friendly.
Negatives....wine a bit expensive so we opted for the house wines. They were good, and you don't come here for the wine anyway! The toilets weren't as clean as they could have been.
Overall I would jump at the chance to eat here again.