[Stef]

I did some testing and tried to start the car with the key internals moved about 1cm to the back. The car did not start.
The moment you turn the ignition, the transponder is detected, if no detection, NO start.
Here a picture of an (2004) Accord key and a Civic key ( to the right)
You can see that the Accord key has the transponder fixed into the plastic, the Civic key transponder is fixed onto the board.
An option could be to remove the transponder from the board and fix it inside the key plastic....
I ordered the Ebay one also, so I could be in for a treat. Anyone else want to test?? ( PS the original key costs 125€).
Also the extra metal of the flip key could affect the transponder signal.