I have been using an unlocked 5s ever since it came out. It was my first iPhone and still performs all function as well as it did back then. However, due to my international travels & limited LTE & radio bands supported by 5S, I decided to upgrade to a newer model. Due to the outrageous full price of an unlocked iPhone and 4 inch being my preferred form factor my options were limited to the SE model. This was until Apple's website listed refurbished & unlocked 6S. With almost same price as brand new unlocked SE and better support for almost all LTE & radio bands used world wide and also including standard Apple warranty, it seemed like a terrific choice. I decided to give 4.7 inch form factor a try and placed my order on Apple's website. The phone arrived in pristine condition and it looks & works as brand new. I popped in both CDMA & GSM compatible SIM and it works flawlessly. I also installed apps to check the chip manufacturer which in my case is TSMC and battery is also brand new. The bigger screen with 3D touch is a very nice upgrade and I had no troubles adjusting to the bigger size and believe it or not I can still plugin my headphone. Overall, in my opinion, at this price range it is definitely worth every dollar spent.