Well, I tried using the app to enable GPay and then made a couple of POS purchases yesterday.
Everything was smooth and uneventful -- exactly as one would hope. The app correctly indicated update to available credit, instantly.
So far, so good. I cannot see any web-base capabilities which mirror what is available on my Android phone, but perhpas a link will be available when the card and welcome kit arrive, this week.
More to follow....