McKinsey in South America - Top tier MBA?

Hello,

I'm a franco-peruvian grad IE student, actually living in France and doing an internship in Accenture Consulting Paris, specifically in the APLS service.

My career objective is to rebrand into strategy consulting (Big 3) by doing a Top tier MBA, and then industry or start-up. All of this in the latin-american market.

My question is the following:
There's a great chance to get hired by Accenture at the end of my internship, nevertheless I applied to McKinsey Peru (my original country) and I got accepted for interviews. Besides the fact of being accepted or not... Do you think that it is a "smart choice" to change a top consulting firm such as Accenture in Paris, for McK in Peru? Stating it differently: Starting as a Consulting Analyst in Accenture Paris or McKinsey Peru?

It can be quite obvious, as I would like to finally work in Latin-America, but in terms of experience and career growth, I fear that working in a less competitive country might not be that beneficial for my career plans (top tier MBA). On the other hand we are talking about McKinsey...

Thanks in advance for your comments.