I would NEVER train back and legs in consecutive days.... Too much stress on your lower back. If you feel the need to hit the gym 5 days a week check out "max-ot", its a decent basic 5 day routine.
My current routine is Mon delts and arms, tues legs, thurs chest and Fri back. I'm off wed and sat&Sun. I am doing this rt now kinda as an experiment cause I'm just starting to TRAIN again after back surgery. After I get enough size back (avatar pic was taken today, I feel small as hell!) I am sure ill go back to Mon, wed and Friday only. The larger you are the more time you need to recover.