First $1,000 electric bill will cure them of flipping the emergency heat on...
I haven't installed a HP system without a delay and variable speed blower. Combined with proper duct sizing I haven't had any problems. The only "problem" I ever have is from people with fossil fuel heaters that expect a blast of hot air when the heater comes on. I had one nit-wit I had to deal with on that who claimed the heater was broken yet the house was almost 80f when I got there with outside being in the 30's.
"But I don't feel hot air coming out... I keep upping the thermostat but I don't feel hot air coming out... Why am I sweating?"
Wasn't too bright that one...