Without a doubt, one of the best Thai places in the city. They have raised the prices lately, bit it's still fairly reasonable and the place is always packed, so I guess it's still worth it. Panang Curry is great here and the Siam Noodles have a wonderfully massive amount of extremely delicious peanut sauce on them. Beef Satay is also a favourite.
Only negatives are that it's often very loud inside (due to the busyness and a solid ceiling) and you may be seated at a cafeteria style table if you have a small party (but that never bothered me). The waits can also get a bit long and they don't take reservations for dinner.