I used to have him as COD and all went well. Everytime we did a call he had a cheque in full waiting for us.
Then we started doing alot more for him and it became a problem. He would never revise his confirmation for waiting time, redeliveries etc, he would just say "make a note of it and I will fix it when it comes in". Well he never did.
Payment terms became 60-90 days, short paid constantly and having to chase all the time, it wasn't worth the time and effort.