This is my own personal opinion. I believe anytime you have a relationship of any kind with an MSB, you should do the addtional due diligence. Some time ago, I participated with a group of people doing lookbacks. We found that the owner of an MSB had a HELOC at the bank. He was cashing the HELOC convenience checks to fund his MSB daily operations, and also structuring the withdrawals. He was making his payments by check from his personal account at another bank. We found out during the review that the deposits to that account consisted of checks from the MSB account held at yet another bank marked as payroll, bonuses, loans, etc.
I am aware that this is probably an isolated case, but with all of the pressure on banks to monitor MSBs, and all of the difficulty MSBs have finding a banking relationship, I think some of the MSB operators are going to use some creative methods to do their banking.
Politicians are like diapers. They need to be changed often and for the same reason.