I tried that amazon, stuff, and the gluemaster stuff is so much better.
As i said, you use the thick and accelerator, to tack the rocks, and then use the marco powder and thin as the motar.
Its sets so strong that a very long single 1 piece that can defy gravity.
Infact i could progbably even lift it at the arms slowly, and it would probably not break at the joint.
If your going to just tack the rocks and use a putty / filler, then a thick with accelerator is probably the best.
If your going to use Marco Powder and go all bells NSA, then you want both as i stated in my first post.