They both have there advantages, Also seasons and locations are key indicators weather you make money.
Getting setup for mushrooms is simple, inconspicuous, rather cheap. They are not forgiving at all though. You make one simple mistake (I.E. my wife opened the bathroom door while I was inoculating a jar and that one jar in that batch grew green mold.) Only set me back 1 week and like $0.50 tops.
Getting setup for Herbs you have to do all these risky illigal and exspensive things just in hopes to get a decent plant, You are taking a risk for a much longer period of time and the pay off at the end is decent but after all your equipment, power consumption, time, effort and risk. The weeds always end up costing you.
Marijuana imo can be a good indoor cash crop but you have to have serious money to even think about making a decent buck, Mushrooms are the perfect cash crop if you live in the North eastren states and canada thru december-june/july. Once the fiends can get them from the ground, I cut back operations and grow enough cubes for myself and friends.