I have some Dr Earth on hand. I really like Down to Earth Organic. Nothing is ever a perfect substitute for anything else in the world of organic fertilizers, though. Different sources for different nutrients are going to break down and become bioavailable at different rates, making different blends react differently over time.
That said, Matt does some pretty great grows and copying someone with good results is a good place to start, but even he changes up the formula a little from one grow to the next. The goal is to learn how to read your plants and respond to what they tell you they need. Don't get too hooked on doing exactly the same thing he's doing because there are going to be subtle differences even from one pheno to another what their nutritional wants will be. If you experiment enough, you could be the next grower the newbies are copying.
I do love growing with organic fert in coco, though, and I use the heck out of some autopots to make it practically hands off. I've played a bit with blumats, too, and love them. Worth checking out.