And 48/72/120 months (I've only just replaced my Dell Inspiron that has been happily running Linux since 2010). Security updates are pretty slick now, I don't expect them to break anything. Upgrading to the next Mint major version can be a touch tricky sometimes, but same with MacOS.
Once something works (and only WiFi didn't work out the box), it keeps working.
Once something works (and only WiFi didn't work out the box), it keeps working.