Named Constants vs. literals

All,

We've all heard that you should use named constants in place of literals,
but how far do you take this?

For example:

D RECORD_LOCKED C           01211
D FILE_CLOSED   C           01218
 /Free
   Chain(e) %KDS(CustKey) Custrec;
   Select;
     When %Status = RECORD_LOCKED;
      //...
     When %Status = FILE_CLOSED;
      //...
   Endsl;
 /End-free

Ok, using a named constant above makes a lot of sense.

But what about literals used in API calls?  Does seeing STATUS,
STATUS_MSG_TYP, MESSAGE_TYPE_STATUS in a call to SndPgmMsg (QMHSNDPM) really
give me anything over just seeing '*STATUS' as the fifth parameter?

What are your standards?

Thanks,
Charles