If that's all you have time for, by all means do it. Remember any exercise is better than no exercise. Most people find they make some progress on that kind of workout for some period and then reach a plateau, which is not all bad. At least you are not going backwards. If you are pressed for time, there are other short whole body workouts you can do, like circuit training. Or you can just do one body part per day and keep the number of sets low to keep the workout time down. Just try to choose the most effective exercises. Most people could make pretty good progress doing 2 lower body (1 quad/1 hamstring) and 2 upper body (1 pushing/1 pulling) exercises 3 times a week for 2 sets of 12-15 each. That should take no more than 15 minutes with a 1 minute rest between sets.