Came here to ask about this myself and since there's a huge thread on the topic already, I'll just add my voice to it.
Downloaded and installed the demos for the new versions, and was quite annoyed that it just installed onto c without even asking. I have a separate ssd where I like to keep my installs. Luckily you can just go into Apps & Features and move the install to another drive, so that's what I did. Just a bit annoying that you aren't given the option during install. I can imagine many people not even bothering to go find out how to move apps between drives, since it's not a feature that comes up a lot.
