Beeing someone who has written quite some lines of C code I'd say this description as a whole is correct, although I never thought of pointers and references as beeing almost the same. But that's more a philosophical point of view. When it comes to the machine level, the general statement holds.

Concerning the performance issue, the correct answer is: it depends. If you have to walk through a long inheritance tree to check whether or not one object has been derived from the other or not, this is going to cost something. But then again, you are using features (type safety) that aren't available for pointers.

The point is, just as with memomry management, that you save a lot of time for coding and debugging, and you trade that for a (often marginal) degradation in performance.

Hey, my first writeup here. Don't judge to harsh ... ;-))

Cheers

Andreas