Where guys get in trouble with MOA is that many of their buddies talk about MOA like it is inches or they try to figure out how many inches is in 1 or 2 MOA, etc. You really don't need to know that just like you don't need to know that a MIL is approximately 3.6 inches. Don't get me wrong there are advantages to knowing that a MIL is 3.6 inches and an MOA is 1.04 inches at 100 yards but to properly use any angular measurement you don't need to use the inch measurements you need to determine how many units of angular measurements you need to adjust for the correction you need.
For instance, if you measure with an MOA reticle from Vortex you can determine that your bullet hit 7 MOA low and 2 MOA left of center bull. You would then want to click up 7 MOA and 2 MOA right to make the proper adjustment. It doesn't matter how far away the target was from you because you used an angular measurement to determine your error and adjusted your turret in the same angular measurement.
If you try and do this in inches then it becomes much more difficult and screws most guys up.
MOA and MIL are both great if you use them as angular units of measurement.
There are pros and cons to MOA and MIL depending on what you want to do with it but the angular measuring or turret adjusting if done properly works the same with both.
MIL and MIL Rad is basically used interchangeable most of the time.
Vortex make both MOA and MIL reticles.
HTH,