How useful is the AirDNA Market Grade?

[Jack Cannon]

Hey all - I'm new to the game and am starting to get some reps with the analytics tools, specifically AirDNA.  Here's a question for you all...

How much weight does the AirDNA Market Grade have when you all choose markets?  Do you only go for B+ and above, for example?  For markets with worse grades, how do you find the areas within these markets that perform better (or is that possible)? 

I'm trying to get an idea of how I can use this rich data source - especially since they have an API!  Maybe it's possible to automate this analysis such that I can generate a list of markets/areas quickly to focus on. 

Thanks so much!