This review might be slightly premature but it's been 6 days. I probably could have written what I'm about to write, yesterday but I needed it to go through a workday test first.
Anyway:
-To start, I really appreciate the fact that this phone appears to have a little more screen over the 640 and yet, it's not as wide. It feels like home to me because I also own an Honor 8 and this phone basically has the same width (the difference is 0.01 in) as it. I really like how I can use it one handed without having my thumb feel tired.
-The design and the screen are both nice. I prefer IPS so that I don't have to be concerned about burn in but I have to give props where it is due.
-Performance and that 16GB has been nice for me. I haven't found myself frustrated at all.
-Speaker volume is kind of quiet (to me), but far from barely being able to hear it.
-The cameras have been a pleasant surprise. Shots have been a bit better imo over the 640 but I haven't done a shootout or anything of that nature yet between the two.
-The connectivity is pretty good, which has actually shocked me, considering that the 950 and the 550 were both just OK. It did a good job at work (which kind of sucks in general), I was even able to load Instagram Stories at times on my break.
-As for the battery, that's really been one of the not so good areas. I am able to go into the next day, but barely sometimes. If I run it down to 20-25%, I can make it a day and 6 hours, which isn't bad, but I hate to run it down so low. It seems like I have to do the daily charge thing, which is a bummer.*
-Speaking of charging, the charger it comes with seems to take forever to charge wow. I'm pretty sure that my iPhone SE charges faster. Also not a fan of that either.
Overall, this phone has been a surprise in a good way. Windows 10 Mobile has been just fine on it. I am using an unlocked Cricket variant to get Band 12 for data on T-Mobile, no regrets there, aside from no double tap to wake but eh.
*I use the phone in an average way, but since the app for reading library books on here sucks, I have to use Edge to read my books. Edge needs to improve with how much battery it drains when used.