Has anyone used a switch between the ECU battery and the ECU to stop the slow drain of the battery?

I am considering the Booma R/C ECU switch found at this link: http://www.boomarc.com/en/ecu-master-switch

Is there any reason not to do this?

Bob Wilcox once told me the drain on a JetCat ECU was on the order of micro amperes. That optically controlled switch looks like it might have some tiny current draw as well. You really only need to pull the plug if it's going to be months before you fly again.

Looked closer at the instructions. 1 micro amp in standby mode and max of 4 - 6 amps. That won't play for kero start and pretty close or over for propane start.

I never use a switch , Just a nice plug you can unplug . Safe and easy

Here are a few. I have used the Powerbox switch for about 10 years between all my turbines (Jetcat), with no issues. They are good for 20 amps. I use the Emotec DPSI Ampere Battery Backer now on all my jets, dual battery redundancy!!!

Mostly because it is completely unnecessary.

What do you think is inside the ECU to switch off the battery when the rx is switched off?

Odds are that it is a similar component to the one you are going to fit. In fact it might well be better. In that case the net effect would be to draw more current not less!

Trust Jet Cat on this one - I have left mine connected for several weeks in the past and the battery had lost no more than it would have if disconnected.