Men Don't Use Loofas.
I don't care if its attached to a stick so you can wash your back or not. Get a freakin' brush. Better yet.. man up. I have no idea what a man is doing washing his own back anyway. Get one of your wives to do it.
Assuming you have no wives... or otherwise available females... at least employ some male ingenuity. For example you could attach a scrubbing brush to your shower wall and scratch your back all over it. Or... better yet... you could mount a recipercating saw on the ceiling pointing down of course... wire it in... and swap out the blade for a long handled scrubbing brush. Instant back strubber!!!
Failing in all these areas... duck tape a scouring pad to a tire iron.