If you do not like coated cables then you want stainless die-drawn/polished cables. Jagwire slick or Lifeline performance and fibrax pro polished are good examples of these.
I do not think you need worry about .1mm on the gear cable.
Have a few cables, shimano kit (both outer and inner)/decathlon own brand cables/clarke (£1 from halfords) and I can't feel the difference between the stainless steel. Are the extra slick worth the three times the price?
If you do not like coated cables then you want stainless die-drawn/polished cables. Jagwire slick or Lifeline performance and fibrax pro polished are good examples of these.
I do not think you need worry about .1mm on the gear cable.