The ability to monitor multiple servers at once across many different environments is great! It's easy enough that anyone can use it without needing any training or previous experience with APM tools/techniques.
I would like more options when configuring alerts - maybe some sort of GUI? Also, there are no "best practices" guides available yet (it seems). There are plenty of tutorials out there though so getting started shouldn't be too difficult if you have prior knowledge about monitoring software. We've been able to identify issues quickly which has allowed us to resolve them effectively before they become problems within our customer sites.