Log4j is perfect to use in applications where you suspect you have a need to troubleshoot the application in a running environment and don’t know in advance exactly which parts of the application you want to troubleshoot. It’s a bit unnecessary in really small applications since the extra dependency can cause more issues than benefits.
SolarWinds Papertrail is great if you have multiple separate applications and you want to be able to view and search all the logs in one place. It also works well for alerts based on certain keywords in log entries (for example, ERROR, WARN, etc.) Since only the first four weeks of logs are searchable in Papertrail, it may not work well for use-cases where much older log entries need to remain searchable.
It's extremely easy to use. I and new colleagues have never had any issues configuring this tool or setting it up, it works almost out of the box with very simple instructions to follow to configure it to our own environment. I would highly recommend it on that ability alone.
I honestly have never had the need to use the support team, as we have not run into any issues so far. If we did however, judging from how the tool itself works, I don't doubt that the team would provide excellent support for any issues that we may possibly run into.
I haven't used any other software for logging from starting of my career. I am using this one, and I think I don't need to explore any other as this provides me with all thing that fulfilled all my use cases.
I selected SolarWinds Papertrail because it was cheap and already provided precisely the integration surface required by the Heroku stack. It probably provided the least number of 'useful' features (out of the bunch) due to the nature of my logs and the post-mortem updates that were required to make them usable.
