I like that it's easy to set up in our environment allowing us quick visibility into application health as well as an ability to identify bottlenecks or slowdowns before users hit them! It can be costly but has allowed me (and my team) to catch problems early & fix quicker than we would have otherwise been able to do so without this tool.
You need quite some time/knowledge with these tools - not something you just pick-up off of google & start using straight away! We are solving many different types of business process related challenges such as SLA breaches etc which previously was very difficult to find out who did what when and where things went wrong due to lack of data transparency / history viewability within apps.