Using Medifast products

Options
Hi all, I am just starting here. I have been on Medifast / tsfl for about a year-and-a-half, I was really good about sticking to the program at first and I lost 50 pounds but since then I have not been able to be on track and I've gained weight back. My question is, does anybody here incorporate the meal replacements from Medifast or maybe another company into whatever other food you are eating and tracking here? I do like some of the Medifast products and I'm wondering if it makes sense to continue to use those a few times a day and track then, along with whatever else I'm eating.
Thanks!