My question at this point is more what happens when the Google services have issues like it would with Sync for Reddit. When that used to happen, IAP pro users lost their benefits until it was rectified whereas Sync Pro would keep working perfectly.
I'd pay for Ultra monthly regardless since I use the app daily and I'm more than happy to give ~3/mo for continuous development but I don't like that I have no way of preventing data collection/tracking when IAP have issues.