If I'm adding a 'tweener' cruise and looking for value I have no problem with an interior. We always separate the bed for more room.
They are not any noisier than the O/V's located across the hall--noise is determined by location. There are LOTS of interiors on the upper decks.
We have turned down upgrades to OV's if we have one of the large interior cabins on some RCCL ships.