To my thinking, if it does what it says it does, those ingredients would already be used in regular medicine for diabetics.
So my first thought is that it's likely a company that tries to get rich over the backs of people scared of diabetic complications.
At 49 dollars for a month worth of capsules it's not cheap. And - surprise - free shipping from 50 dollars, trying to get you to buy two pots right away.
That said, I haven't tried it and I do not know anything about the ingredients or how they work so I might be completely wrong! But I'd be very sceptical before I'd spend my money on this.