@kelly - Yeah. I think Jamf have a 25-device minimum. I was looking at it for the 6 Macs we had. I don't know if it makes sense to do the iPhones MDM on it, since we also have Android devices that I need to manage. Hmm
The Whole MDM concept isn't new to exchange (though it may be to office 365). ActiveSync for exchange has had most of these features. I think they are just promoting it hoping you will want more managment.
If the sales guy is doing a good job, you don't care where he is or what he is doing. If he doesn't make sales you don't care if he works hard 100 hours a week. Tracking a sales guy can only hurt from a business perspective.