[phenom]

Except for USA and Europe, I never changed my money in SG.
For donkey years, I did the exchange in the country of destination.
For Bkk, I would change enough to last me only at most for the first day and thereafter usually at Timmie's(or is it Timmy?) which is situated directly across the road opposite Indra Hotel in Pratunam, a few steps away from the overhead bridge. They consistantly offer one of the best rates in Bkk. They even give a little bit more on big notes. As the S$500 is no longer available(sigh), bring along the S$1k for that extra bahts.
Some goldsmith shops in the Saphan Kwai area are also good.
I concur that the bank counters at the airport do give better value than the MCs in Sg. As for Sg banks, they think that we are idiots and morons....with their ridiculously low rates.
Ditto for Jakarta(best rates in Chinatown) and Manila(highest value in Balibago); the other cities I go to very often.