I went shopping for a thermostat yesterday and I have noticed there's two parts I can buy for my 1991 Jeep Cherokee 4.0L.

One thermostat comes with a Jiggle Valve and the other doesn't.

I'm wondering, will it hurt my engine/car if i installed a thermostat with a jiggle valve in it (is it more like a benefit). I went to two Canadian Tire, and couldn't find a thermostat without the jiggle valve in stock. They mostly carry thermostats with jiggle valve.

Thanks