It all depends, the best thing to do (and as you are in UC, it will help massivly) is get off the plane and have as quick a walk as possible to Immigration and then hope no other planes have just arrived. On my recent trip through JFK we were in PE and rushed to Immigration and was through within 10mins, but by the time the rest of our plane and another El Al flight that had just arrived got into the hall, the queue was massive and must of been well over an hour wait.
So the sooner you get there the better chance you have of a quick pass through, then you've just got to hope priority baggage works!
Neil:)
Neil