Thanks,
I use Dura Ace bar end shifters, which according to the paperwork that came with them, they say only use Dura Ace derailleurs. I've always thought the derailleur doesn't really care what is shifting it, as long as it can accommodate the chain wrap, which this one clearly can, but maybe they do have something with the dura ace system that is more finely tuned? The cables and housing are all new.