I use Advanced Nutrients for my MMJ and I would NEVER mix it up with other nutrients from other lineups. Why not? Well, let's think about this for a second.
You're growing plants that need certain nutrients, right? And when a company designs a lineup, they design it to work together with the other products. If you throw something else from some other company into the mix, you don't know what's going to happen because the nutrients weren't designed to work that way.
And if you DO have a problem (hint: you will), you'll find out quickly that neither nutrient company can help you because THEY DIDN'T MAKE THE OTHER NUTE. Seriously folks, find something that works and stick with it. You are going to be taking advantage of the research the company has put into the development of their products.
Mixing things up isn't a good idea. Ever.
It's not like mixing up brands of shampoo and conditioner. You're trying to grow living things.