I took a friend to Soi 4 yesterday and had another nice meal. Every time I visit Soi 4 I enjoy their food-it's flavorful and the interior of the restaurant is really pleasant. The only thing negative I can say about this place is the service is often slow. Yesterday we had to wait quite a while before our server approached us to take a drink order, and no one else was in the dining room yet because it was very early.
Bottom line: delicious Thai food, great cocktails, somewhat inattentive service