Read-only price books import faster than standard price books at the cost of editability.
Because of the underlying storage technology used in read-only price books, you can't update individual prices or price tables using the standard Business Manager process. You can update prices by editing them in your PIM and reimporting the price book. In an emergency scenario, you can update a price book in Business Manager using a workaround.
Consider using read-only price books if you’re a third-party PIM for price management and frequently import product prices to Business Manager. We don't recommend this feature for merchants who maintain a few price books directly in Business Manager.
When importing a read-only price book, we recommend importing the price book to your staging instance. Then replicate the price book to your production instance.