This is an awesome lift for the lower AND upper body.
Your back will get a tremendous workout here. We use zerchers often with our combat athletes. It's also a great way to learn squatting technique b/c it forces you to sit back and hold your chest high or the bar will roll down your forearms.
Keep your hands high w/the barbell in the crook of your elbows.
A fat bar is most comfortable, but, you can simply wrap a towel around the center of the bar if a regular bar is uncomfortable.
or, JACK up your GUNS!