I've got one of them too and agree.An old pic of me with my Kramer DMZ 5000. The sustain on this beast was insane, I swear it could last a week. Black Walnut body, ebonol fretboard and the legendary aluminum neck structure/inset.
For me, it was my left ankle. Every time I let go of the neck, the headstock hit my ankle hard.It was, however, very heavy - got to be hard on the shoulder for me over time