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The colour match is pretty excellent but it almost definitely won't match the finish. However if you're doing whole walls (and not patches) I doubt anyone would notice a slightly different finish if the colour match is good.
We used a lot of Johnstone's durable Matt in our renovation and it's been very good so far
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Other thing to consider is the original colour has a mixture of fading and dirt on the surface so a colour that matches it will usually be a pale grey version of the original colour. Most of the time touching up walls is impossible, occasionally it works. Painting entire walls and leaving others unpainted is usually fine even with a matched paint.
After painting the majority of our house in Fired earth paint, (my wife used to work there and got a hefty discount) I need to repaint a few walls. FE paint has a long lead time, so got a colour match at Brewers. What's the chance it matches original paint? Also worth noting FE is £72 for 5l, Johnstones is £44