Groupwise 5.5 on W2K Network

My IT Admin is planning on carring our Groupwise colaberation setup to the new W2K environment. I think Groupwise is a bad product to start with but need some “experienced” advise to give him on why Groupwise should die when we go to W2K. Is anyone running Groupwise on W2K, how stable is it? Has anyone droped groupwise for Exchange or Notes under these sircumstances, Why?
I need to know that the HelpDesk is not going to get flooded with calls when we make the change.
Thanks
HD@RWDI