So.. I have an A1778 that I bought when the 7 first came out on the Apple 24-month plan. I had been on AT&T since before the Cingular days, dating back to the '90s on LA Cellular. My only complaint about my 7 was battery life - it's been significantly worse than the 6S it replaced, running about 20% worse, for whatever reason(s). Then the Intel vs Qualcomm info got out and I've always wondered if maybe the Intel modem was the reason (one of them?) for my crappy battery life. I've since switched to T-Mobile because it's just a better deal and I have several friends who are quite happy with the coverage. So far that's working out fine.
Yesterday I decided to march into the local Apple store and see if I could get my A1778 swapped out for the Verizon model, on the premise that I wanted to switch to Verizon (not actually true, I'm sticking with T-Mobile), but Apple sold me an incompatible phone, implying at the time that since it was unlocked, it could be taken to any carrier. The store geek, and the iPhone specialist he summoned, were familiar with the issue but had not yet had a customer try to swap a phone out on that premise. They went in back and came back with a "new" Apple policy on how to handle the situation. The customer is required to pay off the current installment plan, then purchase the "correct" phone, then some sort of return can be done for the original. Funkdat, way too many hoops to jump through, plus I'd actually have to activate the new phone on Verizon for all that to work. They were completely unwilling/unable to simply swap my phone for a refurb Verizon sim-free model, which is what I wanted.
So I decided to take matters into my own hands. I've listed my A1778 on Ebay, where it will probably bring $800. I bought a new A1660 sim-free phone for the full $895 + tax. So I'll eat the difference but it won't be too bad. I'm now up and running on the new phone as of last night, and battery consumption is already clearly MUCH better than it had been on the A1778. Is that because of the Qualcomm chip vs Intel? I dunno, could be other factors at play here - but whatever it is, I'm quite pleased that I went through the hassle & expense. And once I go to sell the "new" phone down the road, I should be able to extract maximum value from it since it's the universal model.