We live around the corner from this place, and we absolutely adore it. The waitstaff is unflaggingly polite, the service is quick, and the food is very tasty. The portions aren't huge, but certainly enough for one person. We usually get one appetizer and one entree, and that is enough for two people. We highly recommend the spring rolls, the panang curry with chicken, the yum neau, and the tom yum. We've tried all of the other Thai restaurants in this area, and Chanpen is by far our favorite.
Pros: Tasty food, good service.
Cons: Sometimes odd music choices (seventies soft rock, anyone?)