Hi all - would a set of vrs fabia brake calipers go on a normal fabia comfort model on which all brakes are disc and caliper-thanks

No.

For the fronts you would need to find new hubs from a Fabia vRS/ Polo GTI/ Ibiza FR or Cupra.

That makes it quite a pricey upgrade

If you want better stopping power fit something like EBC groove/dimpled discs, EBC greenstuff pads & BF Goodridge braided hoses................all straight fit direct swap in swap out.............