Motion -> Elk M1 -> ISY994 -> Light Switch (Insteon/Zwave) Response Time

Anyone out there using motion sensors to trigger lights on? I know the guidance is to use occupancy sensors (which are 10x+ the cost) so any real world experience - if so please share the response time once the motion sensor triggers before the light switch turns on. Please share what type of light switch you are using too.

I do this, using Elk motions to set a variable, and a program in ISY to switch on a scene with a lamplinc. Slightly less than a second I'd say.

I do it in my living room after 11pm and in my garage if it's dark out or if the garage door is closed. My dimmers/switches are Zwave, which are directly controlled via Elk (M1XSLZW and VRC0P-1LW). The delay is almost instant - certainly under a second. As soon as I see the LED from the motions, the light(s) are turning on.

I use Insteon MS units and Insteon Light Switches with no Elk in between though. With the usage of scenes Insteon units direct link to each other and there is no perceptible delay, at lest less than 0.1-0.2 seconds.
ISY can then control brightness levels, ramp speed, and time off functions but not conditional logic whether the MS controls the switch.

I've been bench testing my Elk M1 + ISY994izw + Insteon dual-band light switches and I'm really impressed how quick Insteon light switches trigger on once Elk/ISY "see" motion...  It'll be interesting to see how well my whole home setup works (tons of motion sensors and Insteon dual-band light switches)...  I'll keep you posted but for now just pulling wire so it'll be awhile.