I went from a 5 to a 6+ at first with a lot of trepidation. The first week, it felt ridiculous and unwieldy. After the second week, I found that I could so much more with the extra screen space that I would normally use my iPad for.
With more and more activities moving to mobile platforms, I think the larger format is the way to go. I'm awaiting my new 7+ to arrive in a couple of weeks!