Another vote for Rajawongse
A bit late for the original poster, but count this as another strong vote for Rajawongse (Jesse and Victor) --- address on first page or so of this thread. My stepson worked at the BKK embassy for a while and he and his crowd swore by Jesse and Victor. He took my husband there when we visited, and my husband got several suits and lots of shirts. Right before he left that post, he ordered my husband a couple more suits and a cashmere overcoat...shipped to US without any fitting, just based on the notes from our visit six months earlier, and they fit wonderfully! (Yes, they got wrinkled, but hanging out in steamy bathroom took care of that) The fabric selection was excellent, service terrific. I cannot compare with others, since we tried no one else, but you'll do fine here.
Now, we're going back for stepson's wedding, and my _second_ thought was Great! another visit to Rajawongse!