I didn't realize how much the sound of an engine distracted me until I switched to electric. I find the relative silence to be very calming when I fly, so I have no desire to add noise to my model.
I am with you 100%+ on how much the engine noise distracted me, knowing that the power would be there instead of hoping and focusing on every burp, praying it wouldn't go lean and stay there. Being able to put 100% of the focus on flying instead of the engine is a real blessing I had not anticipated when I switched. Even though I still love the sound of a well-tuned IC, especially some of the pipes our local guys use, there is no way will I go backwards.
I would only use this gizmo for trimming. I would probably just tape to a temporary mount on the outside. An esc or timer with telemetry would probably be a better choice except all the ones that I know of are difficult to download the data and analyze it at the field. Maybe I just don't know what is out there.

Tell me, when you mention what you posted to an avid IC flier do you get that "you gotta be kidding me..." look?

Ken