I understand u completely. I was there. My case goes sth like this:
I bought my second SP7 in March. For 2 months it was mostly perfect. I was perfectly fine with soft resetting the unit every morning because it refused to wake up from sleep( the unit started to misbehave about one month in). This 2nd unit was much better than my 1st SP7(which I returned) that had flickering & face recognition issues.
Then one fine morning, this second unit simply refused to wake up permanently. Black screen. No logo. Nothing. I pressed the power button repeatedly for 30sec each time. Then power button + Vol up button for 30 sec each time. Made frantic calls to MS technical support. Nothing worked. So I replaced my brand new unit with a refurbished unit.
The 3rd unit has its own set of problems. But I dread the black screen the most. Hence I am now wasting valuable time visiting forums in search of an ans. I thought I was unique in getting 3 lemons in a row. But reading these posts have changed my understanding. Now my modest goal in life is to dump this 3rd unit (if there is no improvement in the unreliability/stability issues) & learn to be wiser in future.
I hope the MS people reading these posts understand that bad press would one day get you.