2S2P is 2
Series2
Parallel.
Check BrianG Page to understand better
http://www.scriptasylum.com/rc_speed/_lipo.html
Nothing is ideal in our world, runtime depends from ton of factors. From Motor, weather, count in track style, track surface and etc.
In realtively small track where I am usualy run I get with 5000mAh pack 12 min in race condition. In this weekend I ran it on faster track with loose surface and i got 7min of running. 5min less I recorded 1600W peaks in my system.
All comes through experince!