Hey i TOTALLY spaced on seeing your question, my bad! I am currently running this same stem/bar combo on 3 of my bikes and I wouldn't run anything else! Completely sold on the 35mm stiffness! It basically makes the front end less chattery on the rough stuff and forces your fork to do all the work. The bar is just as light as the Enve DH carbon and even a little cheaper!

 Think they'd be any good on a Dirt Jump bike? (Wouldnt be carbon, just 35mm)

 I don't see why it WOULDN'T help! It is 800mm though so I'm not sure how you would like that on a DJ bike---may have to chop it down