Very nice phone. 64 S6 to compare is
$819.99 at best buy. I know the S6 has a better screen, SoC, camera, and better materials but I'm sure all these combine don't add up to the $520 difference between these two phones.
Hell, if ASUS has had this mindset from the start they could've made the same device with slightly better opticals, SD810 (or 808), and better materials and I'm sure the price would've been somewhere between $400-500 which would've made the phone absolutely killer and it'll still be $300ish cheaper than a comparable S6. With that being said, I have to hand it to ASUS, I'm impressed with the Zenphone 2.
It's like One+ and ASUS are the only manufacturers that know how to price their phones right. Google used to with the N4 and N5 but disappointingly so the N6 was above many people's price range expecting something similar to it's older brothers (and the sales data shows). Here's hoping Google can return to form with this years Nexus.