I started with the first, Edit=>Assembly. It is good, but a little clunky. The second is more natural and has more options. It appears the second is the way the software was intended to be used. I had a hard time finding it at first, primarily because it is under the “Draft” workbench. For some reason I had it in my head that drafting meant 2D drawing. Nonetheless, the “Draft” workbench is where the assembly tools are located.
So far, it works well enough. The snap (hold down shift or ctrl) function was necessary to successfully align one part, which was a small hurdle. I have been able to successfully move through my first project. I am getting better and faster by the hour.
There are several keyboard shortcuts which can aid productivity. If you use it enough to remember those shortcuts, you will be much more productive.