Quote Originally Posted by dmantione
The difference is subtle, but "is" is implemented by analysing the virtual method tables, not the runtime type information. So, if you want to avoid RTTI bloat, you can still safely use "is".
I have not looked under the hood, so could you clarify why is does a VMT look up when no methods are involved. is only checks if a class is of a certain type, which seems to be to be a RTTI issue rather than a VMT issue, but maybe I'm overlooking something here.