The velour tunics of Seasons 1 and 2 versus the synthetic fabric used in Year 3: your choice?
I like the synth uniforms for their smoother, more fitted look. They held their shape better.
Shatner, at that point in his life, could make anything look good. But even he had trouble with shrinkage. Note his sleeve length when the landing party beams down in "Miri."
For haute couture, it's the difference between Helen Noel and Mira Romaine.
Maybe the velour uniforms are favored by some for their soft organic look, which so clearly reflected the show's humble budget and homey appeal.