I love mine with one caveat. I came from a 6s and was worried about how Face ID would work. It's working perfectly for me, just as invisible as TouchID. I don't even know that my phone is authenticating me, it's just like having a phone with no security set on it except that if someone else tries to use it it won't work for them.
As for size, I think I got it right between the Xs and the Xs Max. As I go back and forwards between my 6s and Xs the 6s now feels small and a bit like a toy. I'm quite surprised about how noticable the relatively small increase in the physical size and weight is for me. If I put my Xs in my front trouser pocket it feels bigger but not so huge as to feel awkward or feel like it's weighing it down but I suspect that had I gone all the way up to the Xs Max I would find it too big when in my pocket.
Maybe it's going to take a few charge cycles for the battery to get to full capacity but my only disappointment so far (the caveat I mentioned above) is battery life. Perhaps my expectations were too high, or my memory from three years ago is playing tricks on me, but based on the official specs that Apple publishes (hours of video playback, talk time etc) the Xs should be a noticeable improvement on my 6s but I don't really feel it's any better at all than my 6s was when it was new.
Apple have totally nailed things like the best ARM-based SoC out there by a mile, FaceID such a sophisticated technology that works so well, great cameras etc but battery life is the one remaining area where I really wish Apple could move itself out of the "mediocre zone" especially for the mid-sized Xs form factor.
