Let's hear from someone independent:
97% Overall Satisfaction Rate by Parents of Helen Doron Early English Students in Germany - Yahoo! News
It think it should be enough!
I'm a mother of 3 boys and I'm very pleased with the method. My oldest is bilingual and he started with 6 YO with Helen Doron Method.
By the way, I know the teachers personally and they love what and how they teach.
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