Same concern here, the "transfer" thing is very concerning. Say I want to "refresh" data between just two sheets every 5 minutes to achieve "near real-time" sync. That's 12 transfer credits per hour, 288 per day, 8k+ per month, well over the highest plan, and that's just for keeping data in sync between 2 sheets. I have like 50 sheets I connect together using IMPORTRANGE() and other functions, so that probably wouldn't work for us at all.