I did one of the shops where you actually have to send money. The shop location was a large regional grocery store, so I did not have any concerns about safety or whether they would follow procedures. I had to wait at least 20 but not more than 30 (I think) minutes to go back and ask them to cancel the transaction. The total time for all aspects of the shop was about 50 minutes, and for the bonus I received it was reasonable. With the right bonus and the right location, I would do another.
The ones where you have to attempt to bribe an employee are not for me.
Shopping Southeast Pennsylvania, Delaware above the canal, and South Jersey since 2008