Low latency is probably more important to me.
Recently I seem to have a 3 second delay on many VC calls at work (and just for me it seems), and I either end up interrupting people or feeling reluctant to talk at all since it becomes impossible to time gaps and conversations right.
Despite that I get a crystal clear HD picture for all participants, but I'd happily sacrifice video quality (in fact I'd accept audio only in some cases) to get a more real time experience (disabling video doesn't seem to have any effect).