finally. the development for w10 has entered the stage of rtm escrow as reported by wzor on 15 june 2015. (source: http://news.softpedia.com/news/Windows-10-...s-484282.shtml)

following the trends of previous os developments, if you don't wanna deal with left-over bugs, incompatible drivers, etc. which will be fixed mostly by windows updates and respective manufacturers some times later, it's better to give a time frame of few months before you upgrade. of course if you have tested the os via insider program and found nothing in the way, your computer is all set.

yes. note that if the pc oem doesn't provide working drivers officially, you can still get latest ones from respective parts manufacturers. i think any parts that are within 3 years old are still good to get working driver supports.