I'm on Medifast right now, and I should preface my comments by saying that I'm very happy with my program.
I really love my health coach. Plus, the forums are a lifeline for me.
That said, I do have lots of experience with the Diet Direct products if anyone is interested.
Compared to Medifast, the stuff on the Diet Direct site (I bought mostly Wonderslim, Proti Diet and Barislim brands) is super cheap.
Using the hot cocoa for an example, a box of seven Medifast "meals" costs me $15.50. I think you need to spend more than $250 to get free shipping with Medifast. Each serving has 110 calories, 14 g of protein, 1 g of fat, 4 g of fibre and 14 g of carbs.
The Wonderslim from Diet Direct, however, costs $9.99 for a box of seven. If you spend $99 you get $10 off, and shipping is free over $79. Each serving has 70 calories, 12 g of protein, 1 g of fat, 1 g of fibre and 6 g of carbs.
(I count carbs, because I find it waaaay easier to stick to a plan in a mild state of ketosis. I try to keep them under 90 a day.)
I wonder if the slightly lower calories and protein are why the Wonderslim plan has six meal replacements a day to Medifast's five? But in any case, the Wonderslim program incorporates fruit, and that's just too many carbs for me, so I wouldn't be very successful. But it seems possible that a person could sub in the odd Wonderslim meal without harming their Medifast plan.
I do usually like the taste of the stuff from Diet Direct better. I also find their shipping faster.
Here are some of the Diet Direct products I have tried, with my impressions:
Wonderslim Protein Bars: some are good! They are simillar to Medifast's maintenance, one-a-day-bars. I especially loved the coconut and lemon flavours. Peanut butter was not so good for me.
Wonderslim shakes: very similar in calories and protein to Medifast, but about half the carbs. Taste...I think pretty similar to Medifast.
Bari-Wise protein fruit drinks: I have only tried the Lemon Razzy, and I thought it was pretty good. It was a little bit tart and went down pretty easily. Best of all, it only has 15 g of protein and only 1 g of carbs. A nice, occasional change from the thick, artificial sweetness of shakes. These drinks have a much lighter and fresher flavour and texture than Medifast's fruit drinks.
Wonderslim Cappuccino: Isn't as rich and creamy as Medifast's cap, which I love. The Wonderslim was totally drinkable for me, but not the treat the Medifast version is.
ProtiDiet pancakes: I love them with a squirt of I Can't Believe it's not Butter spray. A real nice change from shakes!
Wonderslim yogurt smoothies: These are awesome. A natural fresh fruit and yogurt flavour...I really wish Medifast would make something similar.
ProtiDiet pea soup: now, I recognize that it's a small population of people who are willing to eat pea soup at all, never mind a diet one.

But I kind of like the stuff! I couldn't eat it every day, but once a week or so, it's tasty.
Wonderslim cheesecake: This is really a pudding, with a bit of a cheesy tang to it. It's totally edible, don't get me wrong, and a nice change from regular puddings, which can get a little glutinous. But it definitely won't live up to your cheesecake dreams. It's nice once in a while with a diet raspberry jello. I wonder if it would be good mixed with another pudding, like lemon or chocolate?
Anyway, those are my thoughts. It's so weird, but the idea of eating brands other than Medifast feels like cheating to me...I'm an advertising executive's dream. They did a really, really good job of creating brand loyalty in me. But truly, would it make that much difference to sub in and out? I honestly don't know.
Wouldn't it be ironic if all this stuff was made by the same company, and we just pay more for Medifast because of all the marketing?