Motion detector delay

I have been using Veralite for 2 months now. I am wondering what brand motion detector and light switch will give instant operation. I just installed a linear switch and a linear motion detector and it take about 2 to 3 seconds before it triggers the lights on. I have tried to read as mich as I can but an a bit confused. Also are there any motion detectors that are hard wired that will work with Z Wave?