Well, I'm Thai born and raised with a family that runs resturants in the DC and Bangkok area and this is by far the best food outside of Thailand. I can't say it's the best in the country because I haven't eaten everywhere but out of San Francisco, DC, LA and NYC, this is top 3 on my list. They serve northern and eastern regional cuisine as well as your more usual pad thai, pad see eew (what my chinese friends call chowfun :-). You'd be making a mistake if you only come here for the buffet. Order something from the menu, try something from the regional list cuz this might be the only place you'll every come across it.
Warning: You should order "down" in spiciness. If you're use to eating medium at a 5 (with 10 being barely eatible by a Thai person), then you should get a 3. A 5 here is NOT medium and you can always have them increase the spiciness if it's too mild but you can't go the other way.