Hello Smiler52. Welcome to the EightForums.
Just for technical fun I just did a clean install and logged all time specs.
First I imaged my system with acronis then I inserted an 8 pro bootable usb stick (flash / thumb drive).
Clean install from usb stick to internal ssd to default start screen.
Timeline: 4:35
set usb to boot (first boot device) in bios
clicked saved to bios and boot
Timeline: 4:36
boot to enter product key
Timeline: 4:37
click next > select custom install > delete all partitions on ssd > click next
Timeline: 4:38
screen display "getting files ready for installation" at 15%
Timeline: 4:39
screen display "getting files ready for installation" at 36%
Timeline: 4:40
screen display "getting files ready for installation" at 70%
Timeline: 4:42
screen display "getting files ready for installation" at 100%
Timeline: 4:43
automatic restart computer > booting > enter bios and change first boot device to ssd
rebooting > enter pc name >
Timeline: 4:44
enter user name
system generating welcome screens
@ default start screen
Timeline: 4:45
Total time for clean installation from a usb stick to an internal ssd to default start screen > 10 minutes