I personally did the test between both, I do not need to feel confident, I know that the i5 works great and much cooler, quiet and better battery life than the i7, I can wait an extra 50 seconds for an iMovie project to export.
EXACTLY and i scored a WIN
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16% battery left after 5 hours of Safari browsing (5-12 tabs), music/podcast streaming, iMessage usage (1 chat).
i7/8/256
That's pretty sad.....that i-7 is a battery killer
B/w what are your thoughts on the 512GB SSD...i just bought that one yesterday for my 11' I-5/8GB RAM air.. I was torned off b/w buying a 3.5 pound tall time-capsule 270$ 2TB (that only lets us use that HDD in it for back-up and not really as an external HDD -- i know you can connect a separate HDD via USB but that defeats the purpose of that 2TB just for back-up only...and 6 antenna's for 802.11ac)