It's probably an option between the shiftronic or the manual, it does allow you to shift without a clutch but it will automaticall up shift if you should try to downshift into second while going 80 or so (keeps engine from over-reving). It is not more Effective/efficient than a stick because it's still an auto that allows you to choose gears manually. A lot of manufacturers are offering some variation of this on their vehicles lately, Chrysler even offers them on some of their mini vans, they call it auto stick.
Sorry for the long response, just trying to help out.<img src=icon_smile.gif border=0 align=middle>