I grew up not far from pass grass
We lived about 25 miles out of Eagle Point totally surrounded by BLM.
I could take off on my bike and ride for a lot of miles in just about in direction, no fences, no houses, no Sheriff patrols doing sound checks.
It's been about 35 years since I lived there so I'm sure it's been mostly fenced off and shut down by now.
It was sure good riding back then.
In fact, the AF would have dominated in that terrain as it was a lot of open riding and very fast.
On a bike choice it's really rider choice.
I love my kx500 but not for single track.
Then again my bike is not set up for it and it could be made a lot better.
When I get my AF built I plan on setting it up for single track so we'll see what happens.
I'd be a little leery of the Berg.
They are great bikes but have always been spotty for service and support in our area.
But hey, if you really like it and you go in with eyes wide open, the Berg would be fun...