Power tap vs Kurt Kinetic curve

Has anyone done a comparison yet. I have an old wired PT and the watts were lower as reported by Zwift even after loosening my wheel quite a bit. What will we be using as the standard?

To be clear: Powertap showed higher watts than Zwift

I have done one: https://support.zwift.com/hc/communities/public/questions/201444179-PowerTap-v-Zpower-Comparison

and plan to do at least one more.