Too high disk activity

Yeah, I loved dropbox concept since I knew it, and it worked very well at begining, but little issues like this are driving me to think about alternatives to dropbox.
If somebody is implementing a better usable product, certainly I will consider switch.

I'm hoping that the "Infinite Project" change this performance issues, since dropbox will have kernel access I belive it will be possible to work in a smartest way.
The way dropbox watch for file-changes don't seems to be the best way.

Besides performance issues it has another issues.
Another day I was planning to make big changes in my dropbox file structure, so I fully-synced my two computers(A and B) to make sure computer 'B' had'nt nothing to upload and computer 'A' nothing to download.
So, two computers with "green sync icon" I shutdown computer 'B' and start my reorganization in computer 'A'.
When I had finished with the changes I start computer 'B' to receive the changes, but to my surprise, dropbox start to upload old computer 'B' folders to dropbox again, making hundreds of duplicate files and folders.

I really think dropbox should take care of these types of issues before spend time developing "google drive style" features!