I've been flying with these the past few months. Now can't imagine flying without them. Now I know exactly how much 'fuel' I have on board.
I previously had video telemetry showing voltage and MAH used. But I much prefer the simple display of the quanum unit.
The power consumption to the Tx unit is extremely low. I've forgotten to disconnect the battery to the Tx a few times and left it connected for hours. On re-check, the voltage remains more or less the same!
Thanks for the OP for the info on changing to lighter antenna. Something I've been thinking of doing.