If you do a search here you will find a wealth of info on rotary cutters. Thats what I did before I bought my BH Model 287, which is a medium duty cutter. This was a recent purchase, so Ive only used it a couple times in some field and light brush and it performed as expected. I expect to be getting into more heavier stuff also, but believe the unit will hold up as it is well built for sure. What I do know is these units are getting up into some money when you get past the KK and lighter duty models. The names you mentioned are excellent quality from what I've read, and you will pay for it, though I believe buying quality is the better choice long term. Buy now, cause pricing is only going higher, and there may be some zero % deals on some models. Good luck with your search.