Lrp flow with. 13.5 1s lipo in superstox

[Robocop]

Right here goes
Changed it from a black diamond (which was version 3.0) to the flow,seemed ok to start with but over about 5 meetings during the run on all my lipo packs same motor etc gearing is correct mpr etc same as others.
The car just seems to loose punch,got fed up with it so put my black diamond back in,did not recharge them,car had punch and speed back...

So my question is anyone else have problems or know of people with them..
Thanks