Most of the people think Ielts IDP is easier than the british council. This is not true, both are the agents who are conducting the Ielts test and both are the same level. So you can go for any of them.
Making inferences of which one is better (IDP or British Council) is just a negative statement. Both are comparatively at the same level only differences are if your considering to apply to Australia you would want to give the exam through IDP and if your considering to apply to Canada, UK, NZ you would want to give the exam through British Council. But other than that all the other "facts" are just false.