That's going to look pretty ugly if the airbag goes off, but I suppose you're going to say that you've disabled the bag so that you can divert your attention by minding a lot of useless information. When I have a problem, I run a gauge into the car, otherwise the stock instruments are fine.

As for using the gauge to detect a stuck wastegate, the overboost protection system will prevent that from being obvious, even with a gauge. And if it's stuck open, your right foot will know. Just admit that it's for fun, I can accept that.