I sync directly with the MS server (on multiple devices) and it works well. (and I don't have to worry about it overwriting existing contacts etc) Am I missing something?
I think the issue is this: Currently you can only sync iOS devices with Exchange if your account has ActiveSync enabled on the Exchange server. This is not a core feature in Exchange and requires additional licensing fees. I know we have to pay extra per account if we want to enable ActiveSync with our hosted Exchange service. Enabling Exchange calendar syncing via OS X SyncServices would be allow users to sync their calendars with their mobile devices even if their Exchange account does not allow ActiveSync.
If you're syncing now with ActiveSync it's not a useful feature, but I guess there are people out there who aren't able to use ActiveSync and they're stuck right now.