ORIGINAL: hungryandbroke
In all honesty, I've Never seen anyones plane crash due to low batteries. I Have seen several crashes from a wing flying off in mid-air though.
So to sum it all up, they should invest the $10 in a roll of Duck Tape to secure the wing on rather than spend the $10 on the Voltwatch.
And that's all I have to say about that!
I have seen two planes crash due to receiver batteries being low. In one case, it was a large ~25% scale gas plane, the other was a nitro plane.
In the first case (large gas plane), the pilot had just taken it off the charger at home, brought it to the field and flew it. He forgot to check it first with his loaded meter. 4 minutes of flying and then, no control. It crashed into the ground about 10ft from another club member's truck! Battery pack was intact, he put it on his meter, it was way too low to fly.
In the second case, the pilot checked it before the first flight, flew twice, took it up for a third, and the RX batt died in mid flight. He figured he could get 3-4 flights in before checking his RX pack again, and he was wrong this time!
$10 for a Voltwatch is cheap insurance and piece of mind. It's not just protection for the $$$ you have in your airframe, it's protecting bystanders and their property if you lose control of your plane.