I've always been really grateful I didn't have a penis. I think abaya understands what I mean when I say I've always had a sort of horror at the thought of having a part of my body that stuck out like that (and such an important part, at that). I still remember the feeling when, at about age four or so, I realized I could have been born a boy and just barely escaped having one of those things!
And, even if it was erect, it'd be dangling soon enough. It all seems very awkward. I'm used to being all neat and compact and I just think it'd be extremely unnerving. Once the shock and horror wore off I'd be happy enough to find out what it feels like to use it though.