Our downstairs HVAC stopped working just months after we replaced the upstairs unit.  This time was a ton easier; plug and play.  Power, gas line and ducting; easy-peasy.  Gely, Matthew and I had the old unit out and the new in within 4 hours of the delivery!   Of course saved tons of money.  My neighbors are spending $5-6k on this replacement, and I bought everything for less than $2300.