I agree. The LS-2 specifies a minimum 2,000lbs, which is quite a bit more than the 1400lbs for the 425.
For
@Tchamp's intended use, I would lean toward brush hogging the paths a bit wider and let the branches flop back in to get the alleyway that you want, but I recognize that that is having a hammer and thinking the problem is a nail...
I could see the advantages for trimming trail edges as hedges. Charlie Iliff used to do something similar with a sickle bar cutter he put on his PT (1845?) to cut trail sides for horseback riding. A sickle bar mower is much lighter, but granted it can't do thick branches.
I think that the Lane-Shark is an interesting design, mechanically, with a rotation point and a second hinge. I had been contemplating offsetting my trencher, and this looks like a stiffer way to generate the offset.
All the best,
Peter