I keep HDR off, takes too long, only turn it on when taking something I know I want to print or when the situation calls for it. Otherwise I am set Auto all the way for the default camera. However 99% of the time when really taking a photo I use Camera+
I keep it off. For the most part I like the pictures more with it off. I can always add it later with another app if I want and usually prefer those results.
I only use it with scenery pics. Otherwise, I notice ghost images when people are involved. Remember, it takes 3 pics and if people are walking, they usually show up ghosted.