Fair enough. I wasn't really trying to dig at overall quality of headphones, but rather the quality of the connectors and the fact that the 3.5mm connectors probably aren't the problem for these ranges.
One thing that hasn't been discussed is that of power. Does the Lightning connector have the ability to pass enough current to the external DAC to drive large over-the-ear headphones and generate respectable bass without distortion? Or will the headphones require it's own battery (AAA or rechargeable)?