I do not own 2013, but I do have My Traffic 2010 on my computer back home, which shouldn't be that different.

It has excellent AI coverage around the world.  I notice that for the most part, the right airlines go to the right airports and often the right gates.  You fly to an airport in Russia, you will see Russian aircraft parked at the gates, for example.  Sometimes you see airlines that simply don't exist appearing at the wrong places, but then, the copy I have is old.  It also puts a decent amount of general aviation aircraft as well. 

The AI models have rather simplistic texturing, which sometimes stand out if you look too hard, but that also has the benefit of saving framerates as well. 

I think My Traffic is decent AI package that provides everything you need with a click of the mouse.  The only downside to it is that it has so much AI models that it makes booting up FSX incredibly slow. Adding more AI to the sim too will undoubtedly affect framerates also.

That's just my rundown based on the 2010 edition.  I'm not sure what's new in the 2013 version but I doubt it's all that different.