What we are seeing, original modules that came on the cars from new are most reliable.
If you move a module that was previously shutting down to a heat sink n works fine, connection was likely your original problem (either TFI to dist or harness to TFI).
Oddly, while most never have a problem, ones that do, once they eat one are way more prone to see another failure.
Electronics that come on aftermarket distributors, most unreliable of the bunch. So bad, some don't work from the minute you drop the dist in.