Man, that is not something I know too much about actually. I almost always do squats with free weights, but I have terrible knees and try to control my rhythm and motion at all times. Squats in general are great and I did do some front squats but mostly stuck to back, just because it seemed easier to control my posture when doing them. Everything I did while peak lifting I just kind of gleamed from reading other articles so if I didn't know how to do an exercise right I didn't do it at all. Front squats I couldn't get the grasp on at all really, so much technique to do it expert right, but from what I understand it can be better for your lower back and reduces risk of injury, but I also know dudes who do back squats and have for however many years they have been working out, so you know... As far as ratio's go, no clue.