Hi,
I tried the Gaurdian system without success. I had two units one for each of electric planes I fly at the local field which wont take jets. I struggled to get them both to seem reliable even though they were updated to latest firmware etc. One refused to switch off at all yet all other functions seemed Ok and the other switched on and of intermittently on an irregular basis. I did not thnk they were for me YET, I have to admit when I went onto a forum to try and corrrect this there were glowing reports.
I bought mine on a "Royal pastime" website and could not be bothered to go through the convoluted returns procedure so it was the bin !