It is terrible advice to change your money on the street. It is illegal. The reality is that since the Jamaican dollar became legally convertable there is no honest reason for anyone to give you a "better" rate than the cambios or banks.
The only people who need to exchange money with you are legally unable to do it in a cambio or bank because of the money laundering laws. If you choose to change money with someone in the street, you are dealing with someone outside of the law. There are serious money laundering laws that have been implemented since 1998, and by exchanging money on the street - you are actively participating in a serious crime. Money laundering crimes can draw a fine not exceeding one million dollars or imprisonment for a term not exceeding five years or to both such fine and imprisonment.
As side note, just the other day I was talking with a female tourist who thought she was getting a great deal to change money outside the cambio. She said she counted out the money, then somehow received less than she had expected to receive. After she discovered the "error", she went back to the money changer and demanded the rest of her money. To make a long story short, she ended up getting a punch to the face when the problem escalated into a drink throwing session. She had no legal recourse since she was engaging in an illegal activity.
So in addition to the fact you have a very strong likelihood of being scammed, you also face the chance to have a vey costly five year "vacation" at the institution of someone else's choice.
Changing money on the street is terrible advice...
