*** This information is now obsolete as the free upgrade offer has ended ***
If you are running Windows 7 or 8 I highly recommend taking advantage of the free upgrade to Windows 10. I have performed the upgrade on a number of PC’s without any major issues. There may be the odd driver or application that needs to be reinstalled but on the whole the process has always been relatively painless.
The free upgrade offer expires on the 29th July so what are you waiting for?