I like that it's easy for me as an editor or producer who works remotely, because there are no more file transfers involved when working with clients! It also makes scheduling meetings much easier than having them all at my desk (which would be ideal).
There isn't anything really bad about this software - just keep using your current program if you're happy already :) We have been able solve our problems of needing files from editors/producers quicker without any delays by simply uploading directly into their account instead of sending over FTPs etc., which was taking hours sometimes up until now!!