I hate playing the refurb game. You are almost never guaranteed to get a working phone again until they decide they cannot resolve your issue with constant replacements. For the years I had Verizon they made me jump through hoops to make sure I didn't do something to the phone to void the warranty. (Good for them actually) I don't mind refurb phones, but then I got one that had a pubic hair on it and the phone itself was dusty. From there I got another replacement device for the issue I was having and it too decided to give me fits. Back then stores would actually take some time to look over your phone. If you got a manager with more sense than he had time to actually help you, you'd walk out with a new phone. That's how I got my wife's BlackBerry Storm replaced with a Storm 2.
Never go into a store or a phone call with a carrier with the attitude or even the perception that you want something for nothing. Once they have that perception you won't get anywhere. I used to fight on the phone, yell and demand things like I was more important that life itself. But then I would normally waste two hours of my life troubleshooting with tech support reps and complaining about the price of tea in China. Eventually my wife stepped in and told me the honest truth about my "success" with customer service departments - I continued to talk until they couldn't do anything but appease me to get me to shut up. I would also get them to crack, yell at me or swear, etc. Eventually that would do one of two things - villify me in the eyes of my wife or the very people on the phone trying to help me or get me out of contract without a term fee. It usually did both.
If I get the 7.8 on my Lumia that is great. If support lags on this phone I might be tempted to go elsewhere. The Nexus 4 unlocked will be $350 - and while that is sleeping with the enemy it is a device that will be supported by Google directly and isn't carrier branded. But, if for the same price I can get a Lumia 920 off contract I could go that route as well. Just depends who is willing to play ball with me.