If Sideshow matches the prototype cut and sew, people should be pretty happy.
Here's where I see the biggest difference between HT and Sideshow on clothes, and not just look, all figures, Sideshow seems to use thinner fabrics, which can ultimately look a little better to people, like the case of Luke, or look a little off, like Darth Maul, HT uses thicker fabrics, not too thick, just thicker and it can have different effects on the overall look, you usually wouldn't notice because you're only judging and HT figure, but when the two companies make the same piece, these differences stand out more.