I have the same experience as @Lgkahn.
My turn on lights from motion or open doors is instant.
I had the V1 hub and an early adopter of V2 and V2 is better than the V1 hub.
The V2 has a better antennae then the V1 hub.
Delay can also be caused if there are signal problems in your network.
I placed my hub in a central location of my house on the ceiling.
This helps the signal.
Also, some scenarios will work better than others.
Basically for controlling lights in a garage I had to replace a solution that involved a minimote with an older generation wired zwave light switch. I say older generation light switch, to emphasize that I did not need the zwave radio of the current generation of ge light switches or zwave plus, just something a little better than the minimote to have a reliable signal.
For, example, initially I had a minimote attached to the wall in the garage to turn on garage lights.
For whatever reason, the minimote in that location has poor signal and created delays in turning lights on and off.
Even worse, it seems that when the minimote has poor signal it might send the off or on signal multiple times. So not only delay, but sometimes I would click on the button, and after a delay, the lights might toggle on and off for a while.
The minimote solution was a lazy solution instead of placing a wired switch in place of the original dumb switch.
I replaced the minimote with an older generation ge zwave wired light switch that I purchased on sale for $10 at lowes and now everything is instant in the garage.
I was able to repurpose the minimote and place it on the wall in the office which is really close to the hub and get fairly reliable actions.