The method via extended tags (or via the Tag Panel) has some extra code in place that makes updating the File List during the process much more smoother, especially when scrolling the list while the process is still doing its work.
The method via actions doesn't use this extra code at the moment. I should probably should also add it there, but I prefer the speed of operation over the ability to smoothly scroll the File List, so unless nobody reports this as a bug ... 
This already should give you an idea about the pros and cons. Both methods are using the same code paths to actually write the files, so there is no difference in the result of both operations.