It depends on your usage and the frequency of your rotary encoder: Because mechanical, you will need to debounce the signals imho. And the signal frequency is probably so low that using interrupts does not make much sense. What I use for such things are normal GPIO pins (polled) with a debounce state machine. That has the advantage that you don't need precious interrupts and you don't run into a 'death-by-interrupt' situation.
I hope this helps,
Erich
