Hi guys, Just wanted to share my opinion about the aftermarket battery GoolRC 5400 mAh 20C. I received the battery and when I pushed the button on it once to show status of charge it went 3 bars out of 4. I decided to charge it anyway to make sure its safe to fly. When I began charging the leds started moving on the battery but when they were all lit up the red led on the charger turned green for half a second and then it turned back to red and the leds kept moving on battery showing that its charging. This was constant until the battery was fully charged and all leds on it went off (around 30 minutes). It scared me a little but the battery and the charger didn't heat up at all so I decided to give it a try and fly it. Now another small issue the battery isn't fitting perfectly in the Phantom so I had to push it quite hard a few times and use some plastic safe vaseline and some contact cleaner on the battery contacts. After a few in and out movements it was similar resistance to regular batteries (which now slide in and out easier due to the fact I've worn out some plastic strips inside ...). I went outside to a nearby field and used my 9443 props because I didn't want to damage my 9450 set in case of a crash. The flight was perfect (no warning at all) ! I was flying from 100% to 20% (landed at first warning 20%) and the time was 21-22 minutes maybe 2 minutes more compared to my original batteries. I pushed it quite hard in ATTI mode to check if nothing strange happens (red lights sudden power loss etc) but it was perfectly fine. Went back home to charge it after a few hours and it took around 30 minutes to reach 44% and that also scared be a bit because I think was really close to the edge when I landed. Not sure tho ... isn't the DJI VISION app and the Phantom itself measuring the battery voltage and shows the % remaining according to it ??? Connected it to a computer (with DJI Assistant) and the fun part shows up the battery is reporting itself as 6200 mAh battery and I received a warning that battery is completly depleted (140 mAH left) but the voltage was 11.5 ... another question mark here... Also did check for updates (wouldn't do any) for the battery but found nothing. The voltages were a bit off from eachother maybe 0.05 volts apart. There also were some cheap stickers mounted on top of existing one on the battery with different C rating and texts but I removed them just for fun Overall I need to get maybe 10-20 flights with this battery only to make sure its reliable and I can climb higher and go further ! I was only flight at 1-2 meters altitude and 50 meters distance so in case of a sudden failure I wouldn't damage the aircraft/props/etc. I repeat myself the flight was 100% fine but I'm still afraid to fly it like my regular original batteries (like going 2-3 km away over lakes and stuff). Will try to update this thread after I have more flights on this battery !