A lot of them track for validity in your postal code. I just put in my mall's.
Also, when peanut labs ask you if you or anyone in your family works in an advertising agency etc, answer none of the above.
PeanutLabs is always good; other two are scams that ask for your phone number and sends you $2 text messages daily or have you complete 2 silver 4 gold 8 platinum offers that require cash. Each.