I agree with both of you. I don't think a Linux system should be too concerned about DOS filenames when it comes to the ancient 8.3 naming scheme, but I believe that some characters simply shouldn't be part of a filename due to their potential to cause trouble with applications that make special use of those characters.
Although technically the only character you can't use is slash, I think space, semicolon, asterisk, exclamation, question, percent....blah blah, blah, all should be avoided in my opinion. The only non-alpha-numeric characters I use are underscore, hyphen, and dot (though I have some older files including brackets....haven't had issue with them yet).