I'll just post my experiences to add to the stats:
2011 Macbook Pro 17" with all the trimmings and cost me about $3500 as I recollect. Worked a treat for 2 years, then fizz, total failure (I do note remember the exact symptoms). New logic board under my 3 year Applecare warranty.
At 3yrs+1 month, pink and blue pin striping screen followed by white fuzz (preceded by weeks of suddenly disconnecting external USB hard drives). Managed to reboot a few times sufficient to retrieve everything that wasn't already backed up. Fortunately I was a few days from completion of my project in a small island in the Pacific and left early, with apologies to the Client.
Into the Apple Service Centre and new motherboard: initially charged for, but later I was advised they will refund. Flew back from overseas where I was on my new project,to collect it and return to my project. Total downtime 3 weeks.
As soon as I got it back I knew things were not right, as the USB drives were disconnecting. After 2 weeks: pink and blue pin striping and lockup on boot; when I managed to get it to boot (after 12 hours) Photoshop reported it did not like the graphics and would drop down to a lower resolution. Then crash again. So back to home base AGAIN (apologising to the rest of the project team for abandoning them).
Apple store here have it back and have it on test but they are saying I will have to contact Apple as they are not authorised to replace the motherboard for a third time (the technician seemed "quite familiar"with the problem, after initially suggesting that it was my external USB drive that was the culprit, though and I had booted up in the shop without the USB drive and demonstrated the pin-striping boot failure!)
So what to do. Dump it in the trash and buy a new Macbook Pro with a smaller screen and with no significant improvement of value to me? The 15" with all the trimmings is going to cost me $3500 which I will willingly pay to be fully productive, but Apple for me is not longer the bedrock of reliability. I can't go back to Windows. Should I but a Dell Alien and install Linux? Totally undecided. Not a happy bunny.