In recent years I've found the US immigration to have improved massively and to be generally very helpful and friendly, queues are rarely that long. Seems to the baggage queues in places like Miami are longer.
Although my best experiences of US Immigration are when arriving on private yachts and having them come down and complete the formalities over a coffee.
The only problems I've ever had are entering on a C1-D, entering on B1/B2 and VWP have always been friendly and efficient.