Ealing - Has anyone got experience (or know someone who has) working as a mystery shopper? Heard tha...

Has anyone got experience (or know someone who has) working as a mystery shopper? Heard that you can earn up to £1200 part time and can take your children and/or spouse with you when you shop and eat out! Sounds pretty good but still not sure. Would be useful if anyone has any comments or advise about this!?