I had an iPhone 6 before I tried the note 5 for 2 weeks, which I ended up returning.
So coming from a note 5 and iPhone 6 I think I can say the moto x competes with them and in my opinion is at least better than the note 5. TW makes the note 5 a really ****** experience with the all the stuttering, also the lock screen is horrid on the note 5.
It's hard to compare it against the iPhone because they are two different OS's. You get more customization with the moto x pure and more google integration, but the iPhone has a quality app store, fingerprint sensor, iMessage, and few other apple only items.
Anyways, I don't think we should even be putting samsung devices on the top 3 because the horrible software, but that's just me.