You know, I've found that doing mostly weights is better for my motivation. Consider this. Beyond a certain point, you're no longer doing cardio to be healthier but just to burn the calories. But you want to have a certain number of calories (between 200 and 500 less than the amount that would maintain your weight). So all cardio does is allow you to eat more. But when I'm putting in hard cardio work I'll think, ok this hour I can work really really hard and burn 200 calories. Or I could just have my eggs hard boiled or on a plate instead of on bread....

Building muscle also does more on a long term basis because every cell in your body burns more calories to run. Muscle requires the most calories to run, and the more of it that you have the higher your needed caloric intake will become, meaning eating the same amount will burn more fat.....