Best security...Apple mind you was going to go enterprise, then pulled back. Focus has been back to the enterprise for BBerry and they are doing very well in that regard. BBmessengar has been a feature for BB phones for a long time. Because the INT (Japan markets esp) like BBM (you can send text and graphics) with no additional data charges...that spawend Apple to come out with their Messenger solution, very similar to BBM in feature set.

I highly recommend a BES solution to my customers because it is the Gold standard AND will work with ALL BYOD devices. Other vendors don't, hence not really an enterprise solution.