Switching sites has nothing to do with receptors. You should switch sites because the more you inject in one place, the more scar tissue will build up, and the harder it will become to push the syringe through the skin.
I would say away from the chest, just seem like a risk that isnt worth it. If you hit a rib, or your sternum or something by accident is gonna hurt like hell.
I don't do this for my family, my friends, women, accolades, pride, or ego. I do it for me and no one else, its just part of who I am.