Super Clean is about 2/3 the strength compared to Black Maxx. I'm not in a "mine is bigger than yours" deal here- just saying you do not want to be careless w/this stuff. I don't know of anything stronger that is available to the general public. Super Clean is on a par w/the driveway cleaner last time I had them both to compare. The DW cleaner cost less then, it has no perfume or dyes, and being a "house brand" it had no advertisement costs to speak of associated to just it.
I had a gallon of the most concentrated citrus-based degreaser you could imagine. I got it from a citrus packing plant worker in FL. This stuff was stronger, but that made it no more useful except if you were using it diluted you'd get more from a gallon.