for me ive got the 4 cell 15-20c 5000mah..the only thing that i can say ...this pack are not 15c....but more 25-30c

ive tested my pack in my hyper7 and wow
my setup:
hyper7
mmmv3(lowest seting at all value)
medusa 2300-70mm
geared 20/46(very fast and high amp draw gearing..i know

)
lipo turnigy 5000mah15-20c
after 12min of hard running on grass field motor was 138f,esc104f,lipo 90f...
the pack was full(16,4) and when ive plugued to check the voltage ..it was 15,3volt...
for the price...they are great

..but lets see at long term use