As a consultant at the end of the SharePoint implementation I must deliver documentation for the farm, the IPs, name of the server, keys, edition, SharePoint specific settings, you name it.
It was a painful and boring c/p job because I needed to search through the SharePoint settings and write everything down in one document. Not to mention if somebody else reconfigured some farm and then documentation wasn't up to date.
Now the documentation is ready in few seconds, and farm differences or changes are detected automatically. I can choose the level of details that will be delivered to the client.
Not to mention if I deploy the farm that is not on the internet and then I am not able to access the farm from the outside and I need to check one setting. I can bring the farm information with myself and load it on my personal PC for later review.
Love the tool. Really makes my life easier.