Engine Undertray

[JTaylor2005]

I am looking at getting an undertray for my car. Has anyone noticed any difference with warm up time. The first 1/2 of my drive to work is very sedate so it takes forever for the engine to warm up during the winter.
It has a new stat iin already and sits at the perfect temp when cruising so that's okay.
It's a case of if im able to get one cheaply I might as well as it keeps the engine cleaner and rust free which is a bonus down all the muddy country lanes I have to drive down.

Thanks