[jrochkind1]

If you've had no problems, that's great, but lots and lots and lots of us have. I tried to summarize (well, that's not the right word, it was at length) here: https://bibwild.wordpress.com/2016/02/18/struggling-towards-...

While integration tests may ideally not use the database (although I find in practice, I think you often need or want to do some 'manual' setup first. But even if you don't, the _other_ tests do db setup and teardown, and the problems start happening when the Rails app is still busy doing something triggered by a test that the test thread considers 'over'. Easy to say "Well, don't do that", but in practice it is very difficult to diagnose, debug, and stop. Using fancy new front-end frameworks like React or Angular tends to make it orders of magnitude worse.

If you haven't run into problems, consider yourself lucky and I don't hold it against you, but many have.