We stopped by for dinner on a Wednesday evening. It was supposedly opening night, but it wasn't busy. We were greeted and seated promptly by a friendly hostess.
The cafe is contemporary and comfortable. Not particularly Hong Kong-ish, but not a big deal.
The service is very friendly and very accommodating. We noticed servers capable of speaking Cantonese as well as Mandarin. Very useful for Chinese customers.
The food selection is pleasingly diverse. Most truly are dishes you'd find in western and Chinese style Hong Kong restaurants.
Overall the food was very well-prepared with excellent ingredients. But none of the dishes we ordered can be said to have been particularly amazing, which is something you want when paying the prices they are asking.
So Hong Kong Cafe's food value is somewhat mediocre, but the service and overall experience is definitely above average. You'll have a very good meal, as long as you can afford it.