With all the brands and variations of AR15s I have had over the years, I don't believe I have ever used the forward assist. I don't even know if they were functional 'cause I never even pushed one to see if it moved!

I've often wondered about this feature... If a round doesn't feed normally for some reason, do you really want to try to jam it into the chamber? If you do, what are the chances that it's going to fire and extract? I think I'd rather clear the one that didn't feed and try the next one.