I prefer to use Eneloop in my AA Tool, not LiIon
but yes, if you prefer LiIon, a usb rechargeable battery makes a good gift package
some of the AA tools turn on some tail LEDs when on LiIon, and I hear this kills the battery pretty fast. some people break off the tail LEDs to stop that drain
also the AA Tool has a lower low mode when not using LiIon… I prefer the option to use lower levels.
another factor that is important to me, is a High CRI LED… the AA Tool does not come with one… though it can be modified, if one has a few tools and skills, that can be easily learned, if want to learn… I will be glad to coach you
here are some photos of the process of changing the LED in an AA Tool