What beach body product should I do next?

I am almost 20 yrs old and six feet tall. I am about two weeks from finishing INSANITY by Beachbody. I have lost 15 lbs and gained some muscle and I can actually see the shape/outline of my abs. However, I have a some excess body fat/skin on my lower stomach because of losing around 50lbs the past 5 years. So I am not sure how to get rid of this belly. Should I do another sixty days of INSANITY or would P90X be better or maybe another beachbody program. If any body who knows a lot about this problem or fitness in general please help me out! Thanks