Air traffic isn't too bad, never much more than a 5 minute delay at the holding points and that's only when there's a dash 8 or something t/o or landing.
That's not what I hear from people who fly out of NZHN. 20 minutes at the holding point is not uncommon. I've even heard of students not getting airborne as they've used their lesson slot up before they've had time to get airborne. Also I have been told that circuit requests for an aircraft joining from a sortie are often refused as the circuit is full.
From what I hear most locals would love it if the Phoenix operation was to result in a reduction in flying at NZHN.