Interesting, AMD have used the word undetectable in their literature. I wonder if it really is? (I have heard that REVO code is detectable, not sure about APR)
If it really is undetectable then that is pretty neat. May have to go invest in this, this way i can put it back to standard when the mrs needs to drive it. Always felt paranoid about giving her control of 320 odd horses.
When switched-on, the Revo code (as any code, afak) is detetectable simply by running a Vag-Com to look for the required boost pressure. Any serious and knowledgeable mechanic about the standard boost pressure will catch it (not every Audi dealer has such competence though).
When switched-off, the Revo code is virtually undetectable.
Except if you un-soldered the stock chip from the ECU and place it on a chip reader, download the code on your PC and investigate it with a dedicated code-comparing tool versus the stock code. Even there, you'll only be able to say the code looks different but it's then another task to identify what/how/where it really does differently (again, as far as I have heard).
Not really for your everyday person, imho [img]images/graemlins/grin.gif[/img]
Eric