Advanced helicopter gunships are very expensive weapons, possibly up to $20 million. There are cheaper drones available for missions like border patrol. There are tens of thousands of dollars worth of drones with infrared detection, which are great for patrolling the border.I think the Z-10s should have given the priority over the VT-4s. We need gunship helis not just for LOC but afghan border sometimes requires quick response. The checkposts can only identify infiltration, they cannot effectively chase heavily armed militants in the darkness of night. The drones are slow / carries much lower payload. Fighter jets are too costly Op / plus not suited for this role of chasing individuals.
See this Apache action on Taliban: