Does anyone have experience with a hosted Exchange provider using absurdly large mailboxes, say between 10Gb and 20Gb each, with a total size of 120Gb in the organization? I am evaluating whether to upgrade somebody to Exchange 2010 in-house, or move them into a Hosted Exchange environment for the long-term. I was looking at AppRiver as a possible solution.

On a similar note, are there any experiences with archiving solutions that hosted Exchange providers offer that you liked?