I use Kasikorn for the immigration deposit requirements and I use Bangkok Bank for everything else that is not under the scrutiny of immigration. Transfers up to 2 million Thai bat at Bangkok Bank. Never had an issue with Bangkok Bank other than a technical glitch that locked it for 30 minutes at 12:00 midnight. Very good service from other satellite branches out of main branch province. Under these preferences no issues from either Bank.

In and out in 30 minutes completed. True about initial limitations for withdrawals and transfers but can be adjusted with discussion at your branch