Yeah its nice, but I dont see it really helping. I mean if you have to keep monitoring your wideband or to rely on a gauge to shut you down to make sure you are not lean, then you are running way to extreme of a tune or not trusting your tuner/set up.
A good example would be JT's car. Unfortunately the motor blew up on the dyno during Nigels FTW tuning when a injector swelled shut. BUT the wideband read rich. Never had a lean spot. So motors can still fail even with a rich AFR. Having this gauge wouldnt have helped.
Its nice. Its cool that it could help, but it may not be able to help in time is the problem.