5000mAh almost 6000mAh and C rating

[Mentat]

I know i have asked something like this earlier at some point, but i am still curious, I have the following batteries and when they get re-charged they get almost 6000mAh capacity put back in. How is this so? also whats the deal with the 20c 25c etc... batteries and how is that factored in. what would be the biggest difference with a 5000mAh 20c and a 5000mAh 25c? I dont think i can tell a difference when running them.


4s1p 5000mAh 20c zippy flightmax

4s1p 5000mAh 25c turnigy

4s1p 4900mAh 25c Rhino (zippy)

5s1p 5000mAh 20c Rhino (zippy) sold to SuicideNeil tho.