I also do flex points just because it gives me more freedom. I know that the negative side of it could be that people eat all "empty" calories and nothing nutritious. I tend to gravitate towards more healthful foods anyway, just because it satisfies me more and makes me feel better physically (no sugar cravings, no energy crashes, no hunger).
Kelly_S has a very good point, maybe you should try both. The portion control on flex is definitely an eye opener for most of us. It's truly shocking to find out what a "serving" actually is and what we're used to calling a serving... which is probably like 4 times more!
Whatever you decide, just make sure it's a plan you can "live" with. If you're serious about losing the weight and keeping it off you have to realize that this isn't a temporary fix, this is going to be your life from now on.
Best of luck to you, we're all here to support you, so if you have any questions, just ask!