Pros:
The display. I've always thought 1440p was excessive, 1080p is that sweet spot for me and it looks pretty good. Personally I think the screen is really bright, I keep mine at a fairly low brightness most of the time. My main downside with the screen is at higher brightness it gets washed out.
Love how the phone looks and feels. It doesn't look like a $100 phone and I like that a lot.
Battery life is great, never have trouble getting through the day.
Marshmallow feels snappy and fast on it.
32GB in a $100 phone AND micro SD? Yes please.
The camera is pretty decent for a $100 phone.
USB Type C, thank god we're finally phasing out Micro USB.
Headphone jack, truly pushing the boundaries. Just kidding, kind of.
Cons:
The speaker is awful, no other way to put it. I hate back facing speakers and it sounds like complete trash even with the Dolby software. Even at max volume I have trouble hearing a lot of videos. I always find myself using my headphones even at home which I never had to do with any other phone. One of the places they cut corners but I really wish they didn't.
Not enough customization by default. I don't really care much for root, I've rooted every Android phone I've had but I've never done that much with it honestly. Just fixing little annoyances that really should be there by default. This is more of a problem with Android in general though honestly. I hate that the default launcher forces you to have 2 pages on the homescreen, I dislike that I can't change things in the notification bar, etc. Little things like that bug me, I feel like I shouldn't have to root my phone or install some random app from dubious sources just to do basic things. Honestly though this isn't isolated to the Zmax Pro, literally every Android phone I've ever owned by default has lacked some little customizations.
Non-removable battery. Pretty big downside for me and aside from the speaker probably the biggest negative for me. Maybe it's just that Samsung batteries suck but I've had to replace my battery too many times on previous phones for me to ever be that comfortable with a built-in battery. I can already feel the frustration when the Zmax Pro's battery starts to have issues, not looking forward to that.
Little software glitches and bugs like the distortion you get sometimes playing games. I use my phone as a flashlight often times when I don't have an actual flashlight on hand and when I press the flashlight button from the drop down, it takes a couple tries to turn on sometimes.
Overall I love this phone, those gripes aside I've had pretty much an entirely positive experience. I don't have LTE issues like other people have, don't give a crap about NFC, never had any major issues, it just does what I need it to do. I'm pretty happy with it, I was coming from $600 phones to this and I don't feel like I've lost much at all and that makes me happy. It's not perfect but I'm glad I bought it. It's going to be my daily driver for awhile, at least until I see if the Note 8 doesn't explode and destroy your apartment.