I generally have not had the Sleep problem in any consistent fashion, just sporadically. But yesterday, I put it to sleep (and had just restarted it for other reasons in the evening), and in the morning, the docked screen was showing a pattern, and my
Surface was rather warm, requiring a restart with the power button/volume button method.
This problem is sporadic so I don't know what to make of it, and I hesitate to return it to the store when I can't demonstrate it. I am overall happy with it, but I must say, I don't quite trust it like I do my work Dell laptop for going to sleep soundly.
I'm also noticing it won't wake up with the mouse movement all the time, and I do CTRL ALT DEL to bring up the screen for my PIN. It's not a restart, but seems like a waking issue.