I always wonder about this when it's discussed... what is the difference? To me it sounds as matter of semantics. It will not change how you view yourself.

I use the "am" form... but eh... it's not all I "am". I am also a Czech, greenparty voter, cat owner, a redhead, eurovision fan, existentialist...

to me more important is how you view implications. If you have an "illness"... or if you "are" troubled. To me the "I am" form is... "well, this is who I AM", deal with it. I am also 5'11 and not that fond of it, but my long legs aren't going anywhere... althought it's not all my identity.

so what is your take on you and your quirk? (since I "have" quirk in my view, not illness). Outside the am/have distinction?