When you say “bikepacking” I am thinking of off-road touring where you need to carry a bit of stuff. These tend to more oriented to all day comfort rather than ripping the downhills.

I don’t have experience with the Rosco, but a friend of mine has a Big Honzo that I have borrowed to try a couple times. I think it is a great bike for ripping on single-track (stable, capable, and a lot of fun) but it is not what I would be looking at for bike packing.

However, if what you are looking for is a bike to get you into mountain biking (without the camping gear) I think it is a good choice. I think plus size tires are great for people getting into trail riding. Opinions on them for more advanced riders is mixed. Some love them others prefer standard size.

One thing to keep in mind about this bike (and I assume the Rosco is similar) is that the geometry and handling is entirely focused on mountain biking on singletrack trails. And for modern mtbs (which are fantastic in this regard) this usually means they are not as comfortable for cranking out a lot of miles on pavement or dirt/gravel roads. As modern “progressive” mtb geometry has gotten better for mtb, it is less good for ”road-ish” use (by “road” I mean dirt and gravel roads, or non-technical bike paths where you are mostly just sitting and pedaling).