Which is best?
This chart shows @cushjbc ‘s factory calibrated MPS (green) and my Wideband O2 calibrated MPS (red). The measurements have been corrected for sea level so the two MPSs can be directly compared.
We only have one adjustment – the screw on the front – so we can’t change the shape of the profile.
To my eye they are essentially the same. At 0inHg they are 0.4% different. Would that even be noticeable in use? At 5inHg they are 0.006% different.
It seems to me that if you have an intact cap on your MPS then great, but if you don’t then Wideband O2 tuning is just as good.