I can’t tell a lie: I didn’t like the Sony a7r IV for my own needs and purposes. But I adore and still use the Sony a7r III nearly every week. The older camera just had better autofocus in my experience. But the Sony a7r IV has much more resolution for those that need it. And they’re both enjoying savings and discounts right now that are hard to turn down. The Sony a7r IV is less than $3,000 right now. Similarly, the Sony a7r III is around $2,100. For the money, I’d probably go buy another Sony a7r III. But at the same time, the Sony a7r IV has some technology in it that the older camera doesn’t have. Decisions, decisions, right?