Both have their pros and cons. Quick releasing beans in the Instant Pot tends to result in more burst and blown-out beans. You can mitigate this by allowing the pressure to natural release fully, but that can take upwards of 40 minutes so it isn't much quicker than cooking over the stove. Of course, if you’re mashing the beans for refried beans or blending them into soup, it doesn’t really matter if your beans are broken up, so the Instant Pot is a big timesaver in this case!