SourceTree has a nice integration with BitBucket when adding a "new" repo.
 
File -> New... -> Remote tab
 
If you have a Bitbucket cloud account already setup it scans for the repositories you have access to and you can click them to clone locally.

Given this nice integration would it not be possible to add the option (like on the website) to pull from a Smart Mirror?  Additionally it could automatically set the "push-url" to the main cloud repo instead of the – IMHO terrible – solution of hand editing the .git/config file?