good point. I really don't know how well they have maintained their dies over the years.
There are two different materials used for making dies...one is extremly hard and is used for regular production. They can be repaired and dressed (to a point)...I used to haul various dies between the auto plants in Michigan to an outfit in Cincinatti that repaired them.
The other material (I forget the name) is much softer and is generally used on low volume parts. These are what the Taiwan stamping operations ( and other low volume users) use as they are cheaper to produce. The downside is, as the dies wear, they don't produce as sharp of a part as they did when new. More fitting will be required when mounting on the cars or the look may not be 'just right'.
That's why original parts...even used ones...are preferred by many.
Now TR2/3 stuff is a little different since the cars were pretty much handmade. The fenders, front aprons and such that are made in England are still built using the English wheel, the Pullmax and other metalworking machines...