Just to add to my last post, we have a favorite restaurant that happens to be in a place with terrible cell reception. With my Droid Maxx (again, it has a "48 hour battery"), when I went there, my phone would drop a good 10% to 20% an hour while we were there. I started turning mobile data off manually whenever we went there to prevent running out of battery.
I ate there last night for the first time since I bought the 6s, and my phone went from 82% to 78% in a bit over two hours.
So, Android stinks at standby, and iOS is better, but - yes, I'm still impressed with the battery life of the 6s. I'm also glad that I didn't get the 6s Plus, as I considered just for the battery life, because I haven't seen any sign (yet) that I would have needed it.