I truly don't think ANY feature on iOS7 is "needed". That's perhaps where our opinions differ the most.
If Infiniti had software updates (oh how I wish they did) then I would weigh the benefit of the updates with the downsides of putting new software on an older car. I go into this KNOWING that I purchased my car "as is" and any update would be just icing. I would answer the question, "Would a slightly slower acceleration be worth the extra cool things?" Maybe yes, maybe no. Wish I had that choice.
I really want the new iOS in the car; if they told me they could add it to my current car (so I didn't have to spend another $35k+)... trust me, I would give up acceleration. Easily.
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