Just to avoid confusing folks ...
No confusion necessary, with folks whom have, been there, done that.
IE:
VLF/Omega...in the past, no problems noted by this Commander.
GPS...likewise.
INS...the same.
So, I would ask, what is the beef?
Follow the respective airline's procedures, and it works out...OK.
KISS (keep it simple, stupid) applies.
NB:
With VLF/Omega, large errors can be noticed on desent, however...Omega is not used any more.
Case closed.