I purchased a second-hand Surface Pro 4 in September 2017. It still had two months left on the warranty and I assumed, stupidly, that I was purchasing a premium product that would provide at least a few years of use. I didn't use the computer very much until I went away for three months at the end of December when it was my only computer.
After about a month of use, it started to blur when the screen wasn't refreshing itself. I added the registry entry to add the seconds to the clock and bought about two weeks of flicker-free screen time. Then the flickering returned, but even worse.
I purchased an upright Cooler Master cooling pad for about £50 which helped a little but it was irritating to have to resort to this and negated the mobility aspect of the computer. For the final six weeks, the computer, on the whole, was a nightmare to use and was like dealing with a temperamental child who could erupt in a tantrum at any moment.
I've been back home for a couple of weeks and I'm back to using my very dependable Lenovo. I've never encountered hardware problems in ten years of using Lenovo products. I'm angry with Microsoft for those months of staring at a flickering screen that gave me headaches and vision problems and for the countless hours trying to find a resolution.