Driving without splash shield on front discs...?

If it rains apply the brakes often. This will dry the pads out. Wet pads have to be saturated to affect stopping power and even saturated brakes dry out in seconds.

As long as it doesn't disrupt function of the braking system you should be fine. I am assuming you are talking about a plastic shield to protect hot brake rotors from water splashing up and warping them?

You'll be fine dude.