So much depends on what's important to you. I've been in the market for several months and have yet to decide what tradeoffs I'm willing to accept for my next phone.
If you trade phones yearly, it probably doesn't matter. But if you tend to keep phones more than two years, then support might be a factor.
Best value for the money depends on what is most important to you.
I admit to being an Android fan who is considering the iphone7. But only because I haven't found anything yet in the 2016 Android phones that speak value to me. They either fall short on hardware or short on OS/security timely updates. Which admittedly is where Apple shines on both counts. Ergo my reluctant interest in the iPhone.
Personally, I'm waiting for the Pixel XL to emerge from the shadows. Should the Pixel fail to interest me, then my choices become really difficult if I hope to stick with Android flagships.
There are some great choices at the $400 point, but they hold little interest for me unless I plan to buy again in less than a year or unless I really compromise on some of my important points.