Double Edge shavettes advantage overr DE?

I got in a new shavette the other day from China. It is one of those that has a hinge toward the back that takes the full size DE blade as opposed to breaking one in half like those of DOVO or Parker. I shaved with it alright until the pin come out of the handle pivot, the "Scales", then I ceased before issues arose and finished shaving with a Feather.

It shaved alright, like I said, but a bit more slowly, since I was being very careful. My question is this: What advantage, other than for doing very fine edging or nape cutting, does a DE blade shavette have over just a DE razor? I can shave about 3-4 times faster with any one of my Gillette or Merkur razors, do it safely and closely. In fact, it is loads easier with the DE razor than either half a blade (which I have used) or this Chinese hinge razor that takes the full DE blade. NOTE: only one edge is exposed, so when it would get dull you would swap it out for the other edge.


Opinions?