There are many better ways to do automatic testing. I've never used Paw for that, and I don't think it competes with e.g. postman on that front, if that's what you're asking.
However, for manual testing / having it write curl commands for you / making JSON really easy to work with by hand, it's fantastic, and I've converted a few people at work to it. Developer is also very responsive and nice to work with on Twitter.
Edit: you can also write extensions in JS for it. Not quite as accessible as e.g. Atom, but still decently hackable: https://luckymarmot.com/paw/extensions/
However, for manual testing / having it write curl commands for you / making JSON really easy to work with by hand, it's fantastic, and I've converted a few people at work to it. Developer is also very responsive and nice to work with on Twitter.
Edit: you can also write extensions in JS for it. Not quite as accessible as e.g. Atom, but still decently hackable: https://luckymarmot.com/paw/extensions/