I just bought the exact same iPhone from Aptronix. Within 15 mins the whole iCloud thing just transferred from stuff from my old iPhone to this one.
This thing is fast! The touch ID takes maybe half a second to open the lock screen( its soo fast that you cant even read the notifications on the lock screen if your finger touches the home button).
Not only that but its current the fastest phone on the market; its faster than the S6, OnePlus 2, Galaxy Note 5, Sony Z5. Dont believe me?
Just check the benchmark score. Yes the phone is super expensive, but it has stuff that no other phone has. Its got sapphire coating on certain parts, fastest CPU, 3D touch(no other phone has this) etc. If you really want the best damn thing which will give you a piece of mind for the next 3 years and’just works’(ahm laggy androids ahm), then go for it:)