+1

If you have a program card or USB adapter you can attach it and feed it the latest firmware, that can get you about 90% sure it will be fine when you re-sell it. But the only way to tell is to put it and do a lap or two, or at least bench test it with a motor that is in spec for the model.

To test you need:

1 - receiver / radio
2 - compatible motor, something like a 17.5 brushless motor will test any sensored motor without drawing more than the ESC can handle. Sensorless as well but may cog.
3 - of course a charged battery
4 - servo - optional to bench test the ESC, but will in some cases expose a weak BEC issue.

This will also mean a lot of soldering practice as well.