It’s easy to use, it has all of your tools you need for data analysis in one place! I like that there are many different ways they can be used as well; not just simple text extraction but also sentiment analytics (which is more difficult with other APIs).
Also some features aren't very intuitive so don' know how advanced users would feel about them - e.g., if someone wants an extractor or something specific from their dataset then this isn't necessarily what's best suited unless maybe its been