A:Answerif you want all the carrier features, you are going to have to flash the carrier firmware for your phone. it will remain unlocked so don't worry about that. if the carrier does something shady to lock it when you put in their sim, they'll unlock it for you anytime after.
A:AnswerYes it does comes with Cable, plug, headphones and warranty. but no transparent protector. you have to purchase that on Bestbuy or other online stores