Welcome to the forums, it's always great to hear about new converts!
I believe
bangsters had a question long ago about exporting userlists & passwords from hsphere. (I only remember because it was a very long thread with scalix & hsphere question's combined.)
While it's normally something that would go on hsphere's forums/wiki, if you have any best practices methods could you make a post on it for posterity? (not here in success stories-the migration section would do)
Glad your 'forced' installation & migration went smooth-lol Once again, welcome to zimbra!