While each of the above Solution has its pros and cons, one huge factor in favor of One Drive for Business is that in terms of syncing of Office documents like Word, Excel, PowerPoint, One Note, the sync is delta meaning that only the changes get synced. So, for a 20 MB file, if the change is 10 KB, only 10 KB will get synced. This is not handled well by the other vendor. Microsoft is able to handle this well since it is also the author of MS Office and hence knows the product better than others.
In addition to the delta sync, there are other equally superb features which make the One Drive for Business the Best in Class Solution: