I've searched this forum up and down but can't find a clear answer, so here goes. I have T-Mobile, want an iPhone 7 but also want the option to sell (if iPhone 8 knocks everyone's socks off next fall) - but don't want to join apple's upgrade program. So I'm wondering whether it makes sense to wait for the "sim-free" version that's been mentioned in a few threads. Other T-Mobilers may also be in the same boat. Anyone know whether the sim-free version is likely to perform as well, or better, or worse, than the currently available "T-Mobile version"? Anyone want to speculate how long the wait will be? I've seen predictions ranging from "a couple weeks from now" to "January". Is it likely to make a difference in resale value? Are all versions (colors & memory) likely to be available in a sim-free model?