Well, I think the 4 XL is going back. In some ways I liked it more than my Pro Max. Build quality is great, screen is fantastic, OS was really smooth (except multitask screen which jitters), and I got it at a price that made it a great value. I also am probably in the minority that prefer Android messaging to iMessage, only because I have more frequently contacted people that use Android and RCS.
But, in the end a few things will stop me from keeping it. The obvious one being battery life. I found myself restricting apps in the background and disabling things to get it through a full day and thats not something I should have to do with a flagship phone. Especially with me being someone that travels a lot for work. Even though I got it to a point where I would get 5 hrs SOT, I just expect more in 2019. And thats with a fresh, new battery. What happens in a year when the battery starts to wear or if Google pushes a bad update that tanks it. Its barely passable as it is.
The other big issues for me personally were video recording is straight up garbage, especially compared with the iPhone. Lastly, I just noticed a drop in quality of apps after bouncing back and forth from Android to iOS the past couple of days. Nothing major, but enough to be noticeable. But what finally made me decide to send it back was I dont think the savings will be that different when compared to my iphone. I imagine when I switch phones around this time next year, the 4 XL will be around $400 secondhand and the market will be flooded. Meanwhile, the Pro Max will still get sold instantly secondhand for probably $900 or so.
I dont blame anyone for keeping this phone. Its excellent and is the peak of android from a software standpoint. Its a shame the hardware side drags it down.