We have done testing with the 3M product, for applications in our fab shop. As already stated, the joints should be designed to accommodate this type product, not just use the epoxy to replace welds. At this time the only area we are comfortable to use it is joining dis-similar metals that can't be welded such as steel brackets on an aluminum substrate panel.
In shear, the epoxy will yield 18 gage and even sometimes 16 gage steel. In tension, depending on joint design, epoxy is not nearly as strong as welds. If your joint will have any tendency to peel apart, the epoxy is not likely to hold.
