Location By IP Range

Sorry I am not finding any recent information on this wizard.
If I understand correctly, it will tag each instance with a location property based on the IP subnet.
Do I need to run it again when new servers are added?
Are there any performance concerns? (We have a large number of non contiguous subnets)
I would like to use this tool to make it easier to identify the locations of our servers
Are there any gotchas with using this wizard?
I appreciate any help anyone can offer.
Thanks

I think I got it, thanks