I dont have mine shut on and off, but when the Relay is on, oh man does it pull on the alternator.
Winshield wipers are useless if the GP's are on in my truck too. They go at the speed of slow, even if i'm driving and the GP's are on, they still don't function right till the GPR turns off.

I've never had mine turn off and on.
And far as my knowledge goes, relay is a relay.
But Jim's got the right idea up above us here.
I'd go out and measure my old GPR, its still .... no wait, I just took it to the scrap yard. It was bad anyways.

Thanks for a good topic of Discussion Jim.