A client would like to assess the impact of several items if they were included in their product, and separately measure the impact of those same items if they were NOT included in their product.
To reduce respondents' time and fatigue, my thoughts are to use 2 MaxDiff questions, both with the same design, and have both questions appear in the same tasks. I'm assuming this would require the use of free-format. Has anyone ever done something like that? Could someone provide some pointers in order to achieve this?