Didn't have the "pleasure" of going to the old one in Sathorn. Havent gone to this one either. But did spend a hell of a lot of time at the Ministry of Foreign Affairs. 6 loooong hours just to get 3 papers stamped and then was told that they cant do it. So I went to the supervisors to complain, then they said "oh, we can do it, we'll do it right now" another 1.30 hours. Wanted to freak out many times.
@tommmmy11 Good question and I didn't have any problems at all. As soon as I said Chaeng Wattana they knew I wanted to go to the immigration office. The taxi driver actually told me about which times are good to go because of rush hour.
It moved last year. This is kind of old news. I recommend not taking the bts first by the way. In my experience, just take a taxi and get on the highway. Takes the same amount of time. Much more comfortable. Remember, Chaengwattana soi 7.