Car appreciation... the aesthetics, the engineering, etc

On the C55 the registration plate screws are not as secure as I would like them to be - they screw into a painted plastic insert:

I'm thinking of using Helicoils to repair the threads - before I do so:

1. Are Helicoils (the brand) the best to use?
   
2. Anyone got another suggestion before I drill and tap this bit of plastic?