At the open day I attended they specifically sold the EMBA as an alternative. I guess they have an easier time filling the MBA class and want increased EMBA applications, for which admissions is less competitive. Of course they also extract more money from EMBAs.
Does the INSEAD EMBA require you to be sponsored, or do they just assume you're employed? Make sure you've done the research -- do you know why you'd choose the MBA over the EMBA, and can you relay this to adcom?
I wouldn't build the application around "MBA over EMBA" exclusively because that may not leave you with much room to sell yourself, but certainly address it directly and make them believe you've researched thoroughly and have a good reason. Adcom don't like to be left nervous or in doubt about obvious questions like that.
When I was on campus I met a 33 year old finance guy who had lost his job and was attending the MBA course. He said he gave very clear and specific short, medium, and long-term goals in his application and exactly how the MBA played into them.
In the end adcom have an obligation to fulfill too. All you have to do is convince them that if they offer you a place in the MBA program that fellow students, the school's alumni, and the recruiters going after your cohort will be better off because you were there, both on graduation day and 10 years later when you've gone on to achieve X with the help of your degree.
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