In fact, we are developing custom monitoring solutions on the System Center Operations Manager(SCOM) platform for our customers and, of course, we are using it to monitor our IT infrastructure. So my feedback will include both parts. We have many cases, when SCOM helps our enterprise customers to address the following problems:
1. Address Availability and Performance issues of the hardware and software components of IT infrastructure (e.g. Exchange, SharePoint, SQL Server)
2. Monitor custom services, created inside organization.
3. Detect IT services outages and quickly resolve it
SCOM is not just a tool - it's IT monitoring platform with great extensibility options and it can solve much more problems with right customization.