Stefan Boon said... Right of the bat: I enjoyed Milford Sound so much more. And I had a partially cloudy, mostly sunny day on both occasions.
Don't get me wrong, I enjoyed Doubtful. It's quiet, beautiful and the boat/bus there and back are a real joy as well. Though Doubtful is bigger in square km, I found Milford to be much more dramatic. The one crack you sail through there is much more grand, steep and awe inspiring than Doubtful. I didn't even mind the other boats. I actually wanted them to be in my pictures because without them you cannot fathom how huge Milford actually is.
Want a quiet trip? Go to Doubtful Sound.
But if you want to witness the most stunning scenery in New Zealand? Go to Milford Sound.