I love this place.
The first time my fiance took me here I was skeptical. It's in the downtown core in a mess of giant buildings. The entrance is nondescript. It just felt like it was going to be "meh." Then they brought us to the back room where it feels like you're entering a mini, magical Thailand.
From there, I was blown away by the friendly service and excellent food. We have been back several times and loved every dish. I would highly recommend the red curry. On our most recent visit last night we had the Two Friends (beef and chicken) and I loved that as well.
This is a bit more traditional of a restaurant than Khao San Road, which also might turn some people off. But does every restaurant have to require a long wait and make you feel like you're not cool enough to be there? What's wrong with feeling comfortable and cozy, and as if the staff really want you to be there?