I recently upgraded my laptop to Windows 10. One disadvantage is the classic minesweeper game has gone away. Fortunately I can still play it on an older desktop running Windows Vista. I recently had to create a new account on this machine because a malware infection had rendered my previous account unusable. This meant my minesweeper win rate statistics were reset and I could easily track my recent performance. I have since played 100 games on the difficult (16x30) board of which I won 43. Most of the losses were due to unavoidable guesses but I sometimes trigger a bomb unexpectedly due to flagging a square as a bomb incorrectly. These errors are most commonly caused by failing to notice a diagonal adjacency. Taking this into account I estimate the win rate with optimal play is around 50%.
As you may have heard Microsoft is offering a free upgrade from Windows 7 or 8 to Windows 10. The offer is currently set to expire on July 29, 2016. One of my home computers, a cheap Dell Inspiron laptop running Windows 8 which I bought in 2010, was eligible for the offer. Due to laziness and paranoia I had delayed accepting but with the deadline approaching I upgraded on July 4th. So far despite some minor annoyances I haven't regretted doing so. Hopefully this will extend the useful life of the laptop with which I have been generally pleased.