I haven't tested this ISO yet (since I have a legit copy/serial) but based on the comments I've read, it works fine.
It tricks the OS into believing that you're using an OEM machine (from the likes of Dell, Lenovo, etc). Whether activation is successful depends on whether your configuration can trick the OS.
If activation doesn't work, there are still ways to have Windows activated using this installer but it may involve flashing your bios.