As others said, being able to audit software and point out bugs is thousand times better than hunting in the dark if there's no Open or Free alternative is available. Compiling it yourself and comparing with the binary you have (reproducible building) is billion times better.
I personally choose Free Software first and Open Source Software second. However, if I have to choose between two proprietary options, I'd choose the source available one. I might not be able to patch/touch it, but at least I can see and verify.
> I personally choose Free Software first and Open Source Software second.
Given that functionally these terms are pretty much equivalent, how do you decide which project is Free Software and which is Open Source? By how it calls itself?
I personally choose Free Software first and Open Source Software second. However, if I have to choose between two proprietary options, I'd choose the source available one. I might not be able to patch/touch it, but at least I can see and verify.