I know the Tubliss system is controversial and I've read a lot of criticisms and negatives. I don't want to start an argument but thought it might be useful for a newcomer to report his experience.
I rode dirtbikes for many years as a kid/teenager. Once had a touring bike and still have a Rokon Trailbreaker. Got a WRR a few months ago to explore the many trails in NW Nevada.
I ride alone in desert country so I carry 4 liters of water, about the same amount of extra gas, a PLB, and survival gear. I'm well over 200 lbs loaded.
I first tried the Tubliss D606 rear on paved roads at 15lbs. Ran fine. Tried 7 lbs on dirt trails. Better ride comfort and traction than the stock rear tire at 14-15lbs. Lowered the Tubliss rear setup to 4lbs. The sidewall bulge appears no greater than the stock rear tire exhibited at 14-15lbs. Rides really nice. I think I could run that tire at 2-3psi but probably don't need to.
With a dramatic lowering of gearing and the Tubliss D606 in the back, I can now climb a lot more of the steep, loose rock trails in my area. When the bike was stock it was ineffective on those trails and I feared I had made a big mistake.
Hopefully the system will last and continue to perform.