It would be good though if there are some reviews of our own on the different brands
so the Gerlach and other boxed 80 pounds types
I have used cheap exhausts on other cars and they have rusted through within 2-3 years. Known brands like IMASAF and Bosal last way longer so for me it is cheaper in the long run to buy decent exhausts and spend less time redoing the same job. So less than double the price but I would expect more than double the life. So it depends what one is looking for.
There aren't that many Coupe owners left that are keen enough to report on their experiences. Exhaust reviews are not likely to be that forthcoming
A 2000€ Coupe will probably also need many parts renewing before it is in a reasonable, usable condition. I have been toying with buying a Barchetta but all the ones near me have been cheap (2-4000€) and tatty. An exhaust, like petrol is a running cost so the average market value is not a reasonable comparison.
But as you say, yours is up and running again so you are good for now.