I've been using the Gym Styles just like they are made: 3 day split. I do one every other day, and do a pure cardio on the alternate days. I try to do one interval cardio, one step, and one floor/running workout per week. A typical week might look like this:
M: GS Legs
T: Imax 2 or 3
W: GS Back, Shoulders, Biceps
Th: Step Blast +Core Max segment
F: GS Chest & Triceps
S: 30-40 minute run + Core Max segment
If you only have 5 days a week to workout, I'd just cut out one of the steady-state cardio days. I've really been seeing some great definition and fat loss by following this rotation.