## 3 Results
### Importance and Perception of Product Design Features
For some features, the perceptions provided by all the technologies are quite similar (i.e., \"Quality\", for which the ratings move a total of 0.24 points, around 3.60), while in other cases, there are more differences between technologies (as in the perception of \"Details\", with a range of almost one point, between ratings slightly above \"Neutral\" in ni_VR and i_VR, up to others above \"Good\" for 360\"). The technology with the best overall perception of the selected product features is the 360\({}^{\circ}\) rotation, while ni_VR is the technology with the worst general assessment, although the difference is not very high. The rest of the technologies have reached very similar mean ratings. The Friedman test for related samples indicated that there are significant differences in the perception of weight (Chi-square (3) = 13.939, \(p\) = 0.003) and in the perception of details (Chi-square (3) = 10.588, \(p\) = 0.014). The post-hoc analysis showed that the weight was better perceived using i_VR than using 2D (\(p\) = 0.021), while details were better perceived using 360\({}^{\circ}\) rotation than with the use of ni_VR (\(p\) = 0.032). On applying the Mann-Whitney U test, a significant difference in the perception of details was detected between AR and ni_VR (U = 505.0, \(p\) = 0.044), while no differences were detected between AR and i_VR. Figure 8 shows the mean rating for each feature and technology against mean importance. Each vertical line represents a design feature, and the technologies are represented by the colored lines. Figure 9 shows the mean ratings for each perception and technology, differentiating by type of product. Significant differences were found between the type of product (Mann-Whitney U tests) in the perception achieved by the following technologies: for 2D, differences were found between both products in the perception of colors (U = 936.5, \(p\) = 0.031), Details (U = 946.5, \(p\) = 0.028) and Quality (U = 937.0, \(p\) = 0.037). In all three cases, the perception in the gooseneck lamp is considered better. For 360\({}^{\circ}\), the mode of use of the sideboard is perceived significantly better than that of the gooseneck lamp (U = 402.0, \(p\) < 0.001). In the case of ni_VR, the materials (U = 111.0, \(p\) = 0.043), finishes (U = 96.5, \(p\) = 0.013), and details (U = 111.5, \(p\) = 0.043) are perceived significantly better for the sideboard. In i_VR, in addition, the materials (U = 80.5, \(p\) = 0.009), finishes (U = 74.0, \(p\) = 0.005), details (U = 60.0, \(p\) = 0.001), reliability (U = 94.5, \(p\) = 0.031), and appeal (U = 96.0, \(p\) = 0.037) are better perceived for the sideboard. No significant difference was detected between the two products in the perception of features using AR. Figure 7: Importance ratings for perception of product features, by type of product. It should be noted that, when distinguishing between products, the smaller sample size is expected to prevent the identification of more significant differences, especially in the case of technologies that have not been used by all the participants (AR, i_VR, ni_VR), but differences were still observed.