Depends on what you want to do/use the FD for and whether routine maintenance creates the opportunity for mods.
My experience was;
Purchased a reasonably good FD (1993) with rebuilt engine,
OE bushings required attention, so swapped all bushes for Poly.
Next Suspension was OE and tired, so swapped suspension.
Brake Discs and pads were OE and tired, so swapped for Tarox discs and Ferrodo pads,
This continued over a few years (usually a winter rebuild) and now I have changed the above parts (including engine/turbo etc etc) for more uprated parts....and this winter changed even more parts.
The trick is selecting the right upgrade parts.
or if your FD does not need parts changing, just enjoy driving it