not accurate, i got friend for who i have installed their W10, they boot in like 2-3 secs, mine boot in like, 3-5 sec ? but i have 4 others hard drive that slow the boot drasticly, when i boot without, its muuuuuuuuch faster.
Either way, i run on win10 since the betas, i tried every recent OS since Vista with their student program, so i had them in advance (RC or Beta versions), and yeah, win10 is a big step forward in Windows OSs, unless you have really specific applications that need older stuff (microsoft money don't run on win10 because it lack support of IE6, unless 8/8.1 for exemple), go for win10, but after you upgrade, do a clean install because upgrades have garbage that still are in corners of your hard drive that gonna slow you down, upgrade is needed only to activate your PC.
Point for the win10 activation: your MOBO serial is saved in Winodws 10 online DB activations, you will not have a key after your activate your windows10 upgrade, unless you change your hardware (most likely, your Motherboard), if you want to wipe your HD, you just need to use a USB/DVD with win10 install, it gonna activate itself.
