Posted 14 November 2012 - 20:37
for me I'm able to install using the key seemingly irregardless of what operating system I'm using. Upgraded from the windows 8 developer preview to windows 8 pro, did a clean install and it worked using the 'upgrade' key. I did not start the upgrade from inside windows 7, I booted up the flash drive from the bios and there was no issue.
It's worth noting that I installed using the 64 bit MSDN version I downloaded off a torrent though, (MD5 hash checker says it's 0e8f2199fae18fe510c23426e68f675a) I don't know what you get when you download it using their upgrade assistant.
You can also upgrade to pro for $15 if you want, microsoft is accepting applications without requiring a windows 7 product key (which I had anyways) ... all you have to do is tell them you bought the PC after June of 2012.
So I've bought 2 keys for 40 bucks and one key for 15 bucks. I would only buy one $15 key per household but people on the deals sites do leech it for all it's worth, it's their way.