Interacting with example products is an essential and widely practiced method in engineering design, yet little information exists on how the representation (pictorial or physical) or interaction a designer has with an example impacts design creativity. This is problematic because without this knowledge we do not understand how examples affect idea generation or how we can effectively modify or develop design methods to support example usage practices. In this paper, we report the results of a controlled study with first year engineering design students (N = 89) developed to investigate the impact of a designer's interaction with either a two-dimensional (2D) pictorial image or a three-dimensional (3D) product (through visual inspection or product dissection activities) and the resulting functional focus and creativity of the ideas developed. The results of this study reveal that participants who interacted with the physical example produced ideas that were less novel and less functionally focused than those who interacted with the 2D representation. Additionally, the results showed that participants who dissected the product produced a higher variety of ideas than those that visually inspected it. These results contribute to our understanding of the benefits and role of 2D and 3D designer-product interactions during idea development. We use these findings to develop recommendations for the use of designer-product interactions throughout the design process.