I've went to both offices, and i must say that Chettawut's office is dark and grimy looking...plus he didnt have a very open and friendly attitude which made it very off putting.
I remembered when i flew in to see Suporn, i was 2 hours past the closing time and he was already out of the office when i got there. so what ended up happening was, he actually DROVE back from his home to come see. It was the sweetest thing ever, that coined it for me. =]