Hopefully there'll be a few people over there willing to try it! It only takes a second to do.
I personally only use one watch, because when I upgrade I give my existing watch to my father, so he has my previous Series 8 and Series 7. So for this test I checked my husband's watch (Series 9) and when I was chatting with a friend this afternoon - who is also quite an Apple Watch fan - I saw their Ultra and asked them to try it. Another friend has an Ultra 2, so the next time I see them I might test it out as well... for science! 😄