One paragraph guide for choosing ShEx or SHACL

A colleague says, "I think I want to use something like SHACL or ShEx.   
I hear you know this stuff. I don't care about whether something is 
endorsed by W3C and I don't know how they work.  I just want whatever 
will work best for me.   Which should I use?"

If your answer starts with "It depends...", then please send it to me, 
off-list.   If you're ok with your response being public, keep the CC 
www-archive.   If you're okay with your text being used anonymously, 
please say so.   If your answer is just "ShEx" or "SHACL", then thanks, 
but that's not useful for me right now.

I say "off-list" because I expect on-list replies to be 
counter-productive at this point.

I'll summarize back to the list.

Thanks, everyone.

      -- Sandro