Once my friends and I were doing homework during our lunch break and a topic came up and it's about why we are studying so hard. And after some discussion, we have decided that the most important factor is: bragging right (I know, it's a bit ridiculous), but then it's kind of true and maybe it's true for shopping as well.
But personally, I'll always choose the product that I like the look of. For example, my laptop. I actually love the design and I still do after five years, but my dad wanted me to buy the laptop he likes so I had to fight real hard to get the one I actually like. And frankly, I don't know that much about technology and I never really read the technical stuff. So I'll always go with design, but the device must function well. And that's about it.