I bought a VA3 (firmware 5.50) 2 week ago and I experienced the following two bugs:
1. after updating the firmware or after a complete battery charge, the tracker suffer a huge battery drain: about 3-4% of charge per hour. The solution is to restart the device and check: usually this solution works and the device start normal battery consuption of 0,5% per hour.
2. I got an additional bug after restarting the tracker due to battery drain: data of tha day are completely lost (steps, floor, resting HR, etc...)
I hope that a new firmware can solve these really annoyng issues.