The absolute worst. Bought a brand new A/C unit from them in 2012 and started pumping money into it 3 years later. Should not have to do that with a 3 year old unit. They don't even want to know you if you do not pay a ridiculous amount of money for their good-for-nothing maintenance agreement. I wish I had known better...It is infuriating to have to shell out money for a relatively new unit!! The one I had before lasted 17 years! What a mistake going with ACE!!!!