I've used armslist numerous times without any problems, but there was one time that sticks in my head. I was only selling a box of ammo and at first the guy seemed fine. It wasn't until we finished our transaction, then he just went off on some weird tin foil hat conspiracy rant about the government while shaking, kinda freaked me out. I have on occasion turned down offers, just because of the way the people act making the deal in the first place.
My son got me started using the Facebook groups for buying and trading all sorts of things, just seems a little more personal, if you can put a name, face, and some friends to someone.
Sorry man, I did not mean to freak you out!!