I have the Mozo Vibe - R. It's light even with steel steerer and stancions. However, it's stiffer than my Manitou Axel Elite. Only problem with my Vibe-R is the lack of dampening. I would pay more for a Mozo Soul if it had dampening and rebound control. But I'm not complaining, I got the Vibe-R for only $50 on ebay. It's better than the Dart II. And way better than the Dart III. The weight (or lack thereof) makes up for the performance loss to the Dart III. Not as plush as the Manitou though. For $50, I'm not complaining though.
I really believe in their transarch approach. Only draw back is clearance on the Transacrch. My 2.3inch is a tight fit. It's fine, but if I went over mud, the arch would remove it.