BTW... if you get the connections wrong on the switch harness all that happens is: Off is on and on is off. (according to the label on the switch itself... if it has one) you plug the battery and plug the sqitch in any unused channel (or the one marked B or Batt) it works fine.
The on-board battery monitor with 5 to 7 LED's... plug it in an unused channel.... It lights up and tells you how much power you got.
when the RX is on.
I use them...they are NICE to have. (you see the voltage AT LANDING, when it reads the lowest.) they drain just 0.5 mah or something like that... essentially 1/4 the no-load current of an idle servo. So what if it takes 12 sec off your max total flight time per charge. USE THEM!