Well, the voltage alarms actually have a loud beeper in them when they dip below whatever value you set them too. So as your packs run down, drive by yourself at a high velocity and listen for it.
2 for $4.40:
https://www.ebay.com/itm/RC-Lipo-Ba...zer-Indicator-Checker-Tester-LED/312818287722
Maybe splurge and buy 4 in case one takes off on you.
2 for $4.40:
https://www.ebay.com/itm/RC-Lipo-Ba...zer-Indicator-Checker-Tester-LED/312818287722
Maybe splurge and buy 4 in case one takes off on you.