It probably doesn't matter at all beyond making duplicates on the FSX map, but from recent experience, having worked on updating RW numbers, navaids and - not least - adding RW10 ILS to EKSP Skrydstrup, I know that it can lead to unexpected results if other scenery includes more or less orphaned bits of navaids belonging to other airports/facilities. I had two other AFCADS installed that contained Skrydstrup ILS code (not Skrydstrup AFCADS mind you, but other Danish airports, and none of them by Vidan

In my (humble and simple) opinion an airport scenery should not include navaids other than those present on the navigation maps for the airport. All those duplicates don't look pretty on the map either.
