The “duplicating” process mathematically deinterlaces the 30 frame timecode to 24 taking the pulldown cadence into consideration when doing so. This way you have a frame accurate tracking of the 24 frame HD masters as well as being able to track the 30 frame sources from which you digitized. This process is done during the duplication from the START to the TC 24 column. The same can be done for conversion to PAL 25fps.
No disadvantage between download as far as the application itself. Even updaters are full installers so no need to have a previous version online in order to upgrade.
Michael