You're going to end up liking it, but not because it's better.
If you are like most people, you'll upgrade your subsidized phone every 2 years. In those 2 years, all top-of-the-line phones will become faster and prettier than whatever you have. If you decide to switch, you'll immediately see how much faster and prettier your new phone looks than your old phone and your irrational self will declare "This is better!" Except...
Somethings will be painful. You might lose all your apps. You might have to get used to a different UI. You might not be able to export your contacts. You might lose your unlimited data plan. There will be annoyances. But, these annoyances are the reason you will like your new phone more than the last one. It's not the faster, prettier. It's the pain. You'll have no choice but to deal with these things. Your brain will rewire neurons and adapt (like a good human brain) and you'll expend effort and energy to conquer these annoyances. And in short order (much less than 2 years), you will master them. And that's where you become attached.
The fancy new thing you got wasn't a new phone. It was a new skill. How to accept and work around the new annoyances. And you'll like it. Every time you dodge a pitfall, every time you become more efficient, your brain releases endorphins to strengthen the neural pathways. It feels good. And because those things you learned with your first phone are disused, the good and bad, they will become unrewarding and unimportant. You'll do this every day, or as often as you use your new phone.
Then one day, you're finally invested in the new phone. You like it and you can wrongly describe why. You've got synergy and efficiency and you've forgotten the pain on the path that brought you here.
And in 2 years, any numerical or feature superiority that might have factored into your decision to switch will be gone. Your phone will be mediocre again. But that's ok. You'll still like it. You now have a brain that likes it, warts and all.
So, just come back and reread this in 2 years. Because
I told you so.