So here's an example of image quality with Battlefield 4 enabled. Now with the normal eye it'll be very hard to detect image quality differences. Above the scene in which we will try out MFAA versus MSAA.
So for the comparison sake we pan and focus on the window with shattered glass, the pointer indicates where we'll be zooming in at, then below you can see a screenshot of 4xMSAA and 4xMFAA next to each other like 600% blown up.
Once we zoom in and analyze a little then we can come to the conclusion that the AA modes are pretty darn close to each others. I have been moving back and forth images and at 2560x1440 it is hard to tell the difference, I however do think that pure 4x MSAA is a notch (slightly) better. BTW it is very hard to do these comparisons as you will never be 100% at the same location the second time you are in a scene so the perspective positioning always differs a small bit. But heck, this is pretty close right ? Lets do another screengrab:
Now in the image above we simply cropped a piece of the wall ceiling. This is 2560x1440 cropped - 100% thus no resizing or zooming in is going on here (this is a 24-bit PNG thus there is no quality loss either). That's as good as it gets with MFAA. If you look at the brightest line you can see the 4xMSAA is a notch better as the edges are a hint softer, but it's pretty darn close (but no sigar).