Network Management systems info needed

[Charles P. Mok]

I am trying to look for information, comments and experience for people
who have worked with and used Sun's Netmanager, HP's Openview, and the
products by Cabletron and Cisco for network management.  If you have used
them, what do you think are their capabilities and how do they stack up
against one another?  Any particularly good or bad experiences with them?

Thank you!
Charles