i've been in that boat, too - inherited a 6S after SO upgraded to an 8 and it does everything i need it to except crap battery life (that's after battery replacement last year). there were a few apps that i missed, but not terribly. it takes calls, it makes calls, google maps work, all of these were not reliable on the nexus 5x i switched from. figured setting up would be about as hard as starting from a wiped android and it's about right.