My oldest Hyperion CX 25C 5000 10S packs are still in use after three seasons and 206 cycles each. I have three of them and one of them was used at the WC 2011.
I also have 4 sets of the same type that is «new». Only two seasons and 152 cycles each.
They all have enough power to fly the F schedule in windy conditions but some of the punch is gone.
Plettenberg Advance and Ulsamer 21x13W. Max 75A in the air measured with telemetry sensor.
Regards,
Henning