I had a chance to play with a 950XL in the MS store in The Woodlands Mall, north of Houston, on Saturday morning. I love this phone! It was running the 10546 build, and was extremely quick to unlock, and open apps. I didn't think to try Windows Hello, and I wish I had. I noticed no heat from the phone, and this was with a phone that had at least 20 apps still running when I when I picked it up. Win10 feels really fast on this phone. I had no issues with the XL size, I did have to use the "hold the home button until the screen slides down" a few times though to be able to do all things with one hand, but overall it wasn't an issue compared to my ancient 920. This phone is comparable in screen size and overall width to a 640XL but is MUCH thinner and weighs what feels like nothing in comparison.The camera opens FAST compared to my 920, and takes really good pictures. The front camera also seems to take better pictures, but I had trouble getting a good one due to the really bright lighting in the store and my glasses. I pre-ordered one. They did not have a 950 on hand, and didn't know when they would have one. They also were not sure if AT&T was going to carry the 950, but were sure they were going to offer the 950XL. I've been "off contract" on my 920 since February, and I'm glad I waited for this phone. The OS still has bugs ( got the resume screen on the start screen at least once) but I'm hopeful they get that sorted next build or two. Did I mention I love this phone?