Underbody paint advice needed

sorry, I'm just not getting this... why are you putting anything other than primer and paint on it ???
Because its not 1974 any more, and for multiple reasons.
It doesn't chip like standard paint, way more durable
-Has sound and heat resistance capabilities. I will also dinomatt floor pan topside and use a heat proof underlay with matting in it
-Some people argue its a lot better than traditional stone guards like Wurth etc
-Modern cars have stone guard in wheel wells and sound deadener to under side of car
-If you have welded in patches etc it neatens up any slight imperfections as it is textured
-Very easy to apply and limited prep although my car was bare metal, acid wash and primed

I am not building a factory car its going to be far from original so not worried about any of that