I have been to Emerald many times in the past 15 years.
They used to have pretty good dim sum.
Now that I'm old enough to form my own opinion, my view of them is somewhat tarnished.
1) the dim sum is often recooked and carted so often that it arrives cold
2) the carts have some of the most inefficient routes, such that it is impossible to get the dishes you want unless you get up and hunt them down
3) slow service - it took quite a while to get change for the bill. i would have thought they wanted a faster turnaround rate.
4) they're not exactly cheap for chinese food.
5) this one really bugged me - last time I went, close to end of dim sum, and they cracked out the vacuum and started vacuuming right next to my table. Not sure about everyone else, but i don't particularly want to eat vacuum dust, nor do I enjoy the sights and sounds.