What do you like best?
I was able to host the app myself for free on Heroku. I could also heavily customize the way that errors were reported to a high degree of granularity. I could customize what and how errors were logged on a per application, per environment basis -- so, for example, I could ignore all errors of a certain type in staging but not production. The available of integrations with applications like Slack also made error reporting extremely easy. All of the errors for all of my applications are thrown into a channel in Slack that all of our developers constantly watch. I also really appreciate that Airbrake keeps track of so many details about the request that generated the error, e.g. URL, parameters, session variables, as well as the backtrace. It will even go so far as to attempt to pinpoint the line in your github repo that threw the error.
What do you dislike?
The user interface is pretty ugly. And the Oauth login with github didn't work out of the box.
Recommendations to others considering the product:
If you can host your Airbrake app for free on Heroku, there's literally no reason to not give this a try.
What problems are you solving with the product? What benefits have you realized?
The key business problem we used this to solve was how to keep track of errors as they presented themselves to users of our systems. It's really easy for errors to just go unnoticed. Manually tailing the logs of several systems, simultaneously, 24/7, and then recording all unhandled exceptions is simply impossible. Airbrake has allowed us to develop quickly and without fear that our users are using buggy code. It has also dramatically lessened the feedback loop when a customer service person reports a bug: we already have the stacktrace thanks to Airbrake!