The Quick Takeoff button in CAMduct does the same job as the Item Folders but with speed in mind when placing Items (straights,elbows).
There are 3 areas that you will work in. The panel on the left is where you select which Item you would like to choose to bring into your job. The bottom panel has a list of what Items are currently part of your Job and the top panel will show a preview of the Item that you have selected from the left panel as well as the fields to edit the properties of the Item like the Width and the Depth.
Once again after editing the parameters you will click on the little green tick in the bottom right hand corner to insert the part. It will now appear in the bottom panel. Where the speed comes into play with Quick Takeoff, is that the top panel stays open and you are able to then insert some more of the same part but maybe with different dimensions. If you change to a bend after a straight, it also remembers what the dimensions were for the previous part so you do not have to double check what part you are connecting to and what the size of the previous part/Item was. Some of the Quick Takeoff components will have 2 parts to it. take for instance the 90 deg Pipe Bend. If you right click on it and select takeoff, you have 2 options. Up to a certain size you will have a pressed bend and larger than that size you will have a segmented bend.