@Vaccano: I have the Nokia 920 that was handed out during Build, and haven't had any issues with it myself.

The biggest issue I had was when I got it set up for AT&T, I couldn't figure out how to turn on the cellular data connection (I could dial out, receive calls, or turn on WiFi and then everything would work).  The fix being to select AT&T in the Settings/Cellular menu then selecting AT&T LTE2 in Settings/Access point menu.  Really should have just read the paperwork they handed out detailing those exact steps.

I do the standard emailing (really like linked inboxes), surfing, texting, twitter, I use OneNote extensively (really like the sync to my Surface)  and I'm often in Baconit (Reddit app).

I have used Skype, Nokia Drive, and the "Find my phone" without issue.

I currently have 18 background tasks running, the battery saver featured turned off and I haven't run into any issues with the phone not lasting the full day and beyond with the caveat that I do plug it in to AC randomly when I actually get to sit at my desk uninterrupted by meetings.