I have read many opinions as to the necessity of completing Check Mig for your entry into Colombia. In my experience Spirit Airlines ask if you have done so; but, does not verify. On my last entry in Medellin I asked the agent in JMC airport if it is necessary and his reply was; you can do so if you like; but, it is not necessary. Your results may vary depending on the agent and airport you use.
As an example I was asked for a physical copy of my M visa via my wife last time I left through the Armenia airport. I have never been asked that before; but, I printed a copy upon arrival home and now carry it just in case.
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