OK, so this is a bit OT. I bought a laptop (ASUS 15" Zenbook UX51VZ) a couple of years ago that came with Win 8. I fully intended to reformat it and install Win 7 but I got a bit lazy and thought I'd give Win 8 a try for a couple of weeks. No surprise, the tiled "Metro" side of Win 8 was as bad, or worse, than I expected it to be, so I tried a couple of the utilities that restore the Win 7 style start menu, finally settling Start 8 from Stardock which was well worth $5. Once I had that installed and configured, it thoroughly changed my experience of Windows 8. I had fully functioning Start menu and the desktop worked just like Win 7. The result: I NEVER have to even look at the Metro UI - it effectively doesn't exist.
The best part is that Win 8 is considerably faster that 7, boots from a cold start in about 6 sec. and it's light years more stable than 7. I work it pretty hard: everything from coding and dev environments to 32 track music production and live DJing and it hasn't hiccuped once .How much of this experience could be replicated in Win 10? Hard to say. the telemetry reporting to MS and their desperate push for the Windows Store are major concerns. If all of that and the other issues with win 10 can be dealt with (with or without help from MS), it could be worth a look but I'm with those that don't find any compelling reason to to upgrade and for now I'm very content with Win 8.1