And it's not pain that goes away quickly and easily, too.
Even a 7.5lb electric guitar with a 3' strap can cause a lot of pain after a few hours. On top of that, I live under the constant threat of chronic back, neck and shoulder pain from a degenerative condition, and it gets a lot worse when I either contort my body to play a guitar that is too large for me or I wear too much weight on my shoulder. My situation is this: I am small-framed, 5' 7' narrow shoulders and short arms. But sold it because I learned I absolutely hate 24 fret necks (except for bass guitars) and I didn't really care for all the switching options in the electronics. Found Olsen guitars and tried out an Ollandoc (please no comments from irate PhisHeads), which was a very nice guitar for the money. I had a DeArmond X-155, sold it because it was just too darned big and heavy.
I will try to update this list as more information comes in.