After a few days of no significant issues and enjoying my Surface, I started experiencing problems. Yesterday evening, I couldn't bring it out of sleep (or whatever it was) state no matter what I did. Had to resort to a volume up + power button combination to start. When I did get to the Start screen, the tablet was unresponsive. Re-booted (don't recall if it was by press-holding the power button or using the volume up/power combo again) and things seemed fine. When I was done using it (just some web browsing), I put the tablet to sleep by closing the cover. This morning, my wife told me that there was a message about the system having re-started (unexpectedly, or something to that effect). Some more minor issues that I've had include were loss of network connectivity due to the wireless network adapter disappearing (resolved by re-booting) and once when I switched from landscape to portrait, the desktop became corrupted in the sense that the bottom part of the screen was inaccessible because Windows only "saw" the desktop extending vertically to the height it had in landscape mode. The display was actually visually split at the point where Windows thought the desktop ended, with the bottom part showing some disjointed rendering of the desktop. Nothing other than the MS updates and the Wintab driver is installed on the tablet that should stress things (e.g. Hyper-V, anti-virus, etc), so seeing these problems has me feeling pretty disappointed. Hard hangs should not happen on a clean system with nothing very taxing going on. Here's hoping that MS fixes things _really_ quickly. This tablet was kind of an expensive a toy for these kinds of issues to be acceptable a few days after purchase. What I'm comparing here is the stability I see with the Surface and several Windows 8.1 installs I've done for friends on desktop systems recently.