I got a few of these batteries to power a Mobula 7. I decided to compare 2 with the 4 that came with the Mobula. After as little as 10 cycles I noticed a significantly reduced flight time in both betafpv 300mah 1s HV lipos. I charged one and then discharged it at 0.5amps on my main charger as a 1s HV and got 260mah out around 80% (I stopped at 3.3v). I then charged the same battery again and flew it. Within 1 min the low voltage alarm set for 3.2volts went off with only 60mah used. The voltage sag is extreme. The Happy model batteries however, are still performing like they did from the start with approximately 2 min and 20 second flight times (flying 1s). I am disappointed in the performance of the BetaFpv 300mah.
These batteries are must haves for whoop style drones like the betafpv65 pro or UR65. Gives you about 4min fly time and great punch.
I have been testing these the last few weeks and you will gain a slight bit longer flight time on a UR65 but only around 10secs if your lucky.