Is Keyword Country a scam? If not, is it a unique tool? Or does it have better, more reliable competitors?

All of these types of guru products are scams.  There is no easy money to be had like this.  SEO is not a pushbutton solution.

The best advice I can give you is not specific to this product, but broader.  Simply put, if you have to ask people if something is a scam, it reveals that you are not knowledgeable enough about the criteria to make the assessment yourself.  Focus on asking why you would need to learn to determine this in the future, and then you'll be much better at sniffing these things out.

Also, beware positive reviews.  Quite often there is an affiliate link involved.