I bought one of those. Found it to be funky and didn't use it. There might be tricks to using it but in my Avistar install, I found it to be cumbersome. An experienced RCer at my field uses Dean plugs on all his planes for charging as well as volt checking. He checks volts after every flight and records. Goes to show, some things work for some and the same things might not work for all. The jury is still out for me on this one. Do make sure polarity is correct.

Happy flying,

Tom