I came to Pai for a late lunch and it was busy, but I was seated right away. I started with the tom yum soup which was small, but significant with 3-4 large prawns in it and a variety of veggies. It tasted very authentic, but for $7 I would have liked a bigger portion.
I got the khao soi with chicken leg (because dark meat is way better than white meat am I right?!) and my friend got the chicken pad thai. The khao soi was delicious, as was the pad thai.
The service is great, my glass was never empty and they brought me a bowl for my bones without me even asking. The servers are very attentive, which can be hard in such a packed restaurant. Would be 5 stars if the portions were larger. You pay around the same price at Sukothai and get WAY more.