Here are some of my initial thoughts, after having owned an S7 and iPhone 7 prior.
It's quick. Really quick. Stock android is so nice. But, I did get accustomed to the gesture navigation of iOS and actually kind of preferred it for many things. Plus, safari is so damn quick.
The camera is what is class as, good enough that you wouldn't have any complaints. IE, as good as my iPhone 7, which is to say, good. Portrait mode is nice (and works well), but haven't had any use for the zoom feature yet.
I can't comment on battery life yet, as I only got it yesterday.
It's very light.
Screen is excellent. But, the jelly effect is really distracting. I was always one to tell people they were overreacting, but it really gives the device a cheap and unpolished feel, which ultimately has ruined the experience for me.
Build quality is difficult. It's easy to hold and stuff, but somehow it feels cheap. It could be due to how light it is, but it doesn't feel as well built as the iPhone or S7, even if it is.
Overall, if you can look past the jelly effect of the display, I think it's a very good phone.
As a student, I paid 400 for mine, and still feel it's a little over priced for the overall experience on the phone.
A flagship phone is more than the sum of its components, and the OnePlus 5 doesn't ultimately add up to anything.