I recommend allowing users to select which drive your program installs on. I am using an M.2 drive for my C: which holds my OS. I have an older one with a memory capacity of only 60 GB. I have enough remaining free space to allow for inadvertent program installations to this drive but some may not. Yes, I realize that newer tech these days has made my M.2 outdated and most new ones are much larger. What can I say, I cut corners for the more important things like mobooard/chipset, GPU, CPU and RAM. It would be nice to have to option to install to another drive so this never becomes an issue.
Thanks