Yar, me loves some Junglas. So far to date, I've owned 3. Them knives are some kind of awesome, and a chopping demon.
I simply love mine, but then again, I love Rowen's attention to detail. And I love big ass knives.
How is the Junglas different from a BK9? Well, there are a few differences, to be sure.
1) The Junglas out chops the Bk9 hands down. No way around it, since its longer, and heavier, it will simply chop through the same media faster.
2) The BK9 is a knife, the Jungals is a machete. Says so in the name. The Rc on the BK9 has an RC of about 58-59, the Junglas, around 55 if memory serves.
3) The Junglas has a very forward balance, thus lending it to be a better chopper, the BK9 has a blade weighted balance as well, just not as much, making it easier to use in a tradition knife perspective
I look at it like this, if you want a chopper than can act like a knife occasionally, the Junglas is your blade
If you want a knife that can act like a chopper when you need it to, the BK9 is your knife.
I own both, and love both, making them blades of a different color.
The Junglas comes with micarta and a kydex sheath, should you so buy one with it, the BK9 comes with grivory and nylon, if you want to upgrade to micarta and kydex, look to spend another $100 or so.
Hope this helps.
Moose