For me, it’s not “real” until its in hard 3d and preferably full scale. Its far to easy to grab a perspective that “looks good” and ignores the nasty angles. Even a spin around “3d” image is a illusion, you need to be able to “feel it” sense its mass its presence. I guess it’s a sculptural thing, where the prime form has a lot of say as to the products feel. I get so much out of a full scale mockup, from its feel to potential problem areas of construction. It helps that I can whip out a full scale of anything up to the size of a refrigerator in a few hours, with nothing more than hand tools and whats lying around. If you have access to ultra high end VR that the aerospace and auto companies use that changes things but even that noting is quite like full scale mockup in hard materials.