In this case I might side with Deere Scotty. If I recall when I was shopping for mine, a JD709 has a 4" cutting capacity. I priced a similar Land Pride with 4" capacity and I think it was more than the JD.
For me it wasn't worth it, decided anything big I would use the dozer or the backhoe. I think a KingKutter would last about 1 minute before it was destroyed.
FWIW, in the end, I did buy a KingKutter 6 footer and it works great on fields/paths and small saplings, but isn't in the same class as a 709 or Landpride 4" cutters. Nor is it in the same price range either! That helped the decision a bit too.