Using crow sure rocks. I have added this to all my jets and it sure makes a huge difference in landing.
In regards to your mate running out of batteries, I have been using the E fuel gauge
http://www.tje.dk/efuelgauge/
Found this to be amazingly accurate and helps to get maximum flight time while reducing the risk of getting a flat battery.
About to have a play with an airspeed telemetry module where you can set the stall speed. Not sure how good this will be but it should be fun to have a play!