Depends on who does them and what method they use. The trick is to make the covers small enough to fit, but only just.
My mate does pretty close to factory style, but obviously by stitching, not the crappy welding that Holden used. He backstitches all flutes to make them stronger so they don't split after a while, plus backstitching is hidden, so you don't see any stitching, just the flute. Genuine Holden upholstery was pretty ordinary and irregular in stitching and shape, but better than a lot of other manufacturers.

Doortrims are better made in a light plywood, than in the original stuff, as it stays in shape better. The steel tops can be attached the same way and then covered normally.

I watch him doing seats and other stuff and it's amazing how it all comes together. He recovered 7 bicycle seats for me yesterday with offcuts he had laying around and they are incredible. Some people have talent.....