IgG tests for the diagnosis of food allergy are of limited value, so I would say not worth the money.
This is a summary of the 2007 House of Lords report on the subject..
"We are concerned both that the results of allergy self testing kits available to the public are being interpreted without the advice of appropriately trained healthcare personnel, and that the IgG food antibody test is being used to diagnose food intolerance in the absence of stringent scientific evidence…We urge general practitioners, pharmacists and charities not to endorse the use of these products until conclusive proof of their efficacy has been established"
http://www.publicatio...dsctech/166/16602.htm
More information here..
http://holfordwatch.i...itional-sciences-ltd/